Re: [PATCH v4 8/8] virtio: rng: Add a random number generator(rng) driver
On Wed, 25 Dec 2019 at 07:00, Heinrich Schuchardt wrote: > On 12/24/19 10:39 PM, Heinrich Schuchardt wrote: > > On 12/17/19 12:52 PM, Sughosh Ganu wrote: > >> Add a driver for the virtio-rng device on the qemu platform. The > >> device uses pci as a transport medium. The driver can be enabled with > >> the following configs > >> > >> CONFIG_VIRTIO > >> CONFIG_DM_RNG > >> CONFIG_VIRTIO_PCI > >> CONFIG_VIRTIO_RNG > >> > >> Signed-off-by: Sughosh Ganu > >> --- > >> drivers/virtio/Kconfig | 6 > >> drivers/virtio/Makefile| 1 + > >> drivers/virtio/virtio-uclass.c | 1 + > >> drivers/virtio/virtio_rng.c| 72 > >> ++ > >> include/virtio.h | 4 ++- > >> 5 files changed, 83 insertions(+), 1 deletion(-) > >> create mode 100644 drivers/virtio/virtio_rng.c > >> > >> diff --git a/drivers/virtio/Kconfig b/drivers/virtio/Kconfig > >> index a9d5fd0..2e3dd3b 100644 > >> --- a/drivers/virtio/Kconfig > >> +++ b/drivers/virtio/Kconfig > >> @@ -59,4 +59,10 @@ config VIRTIO_BLK > >> This is the virtual block driver for virtio. It can be used with > >> QEMU based targets. > >> > >> +config VIRTIO_RNG > >> + bool "virtio rng driver" > >> + depends on VIRTIO > >> + help > >> + This is the virtual random number generator driver. It can > >> be used > >> + with Qemu based targets. > >> endmenu > >> diff --git a/drivers/virtio/Makefile b/drivers/virtio/Makefile > >> index 4579044..dc88809 100644 > >> --- a/drivers/virtio/Makefile > >> +++ b/drivers/virtio/Makefile > >> @@ -9,3 +9,4 @@ obj-$(CONFIG_VIRTIO_PCI) += virtio_pci_legacy.o > >> virtio_pci_modern.o > >> obj-$(CONFIG_VIRTIO_SANDBOX) += virtio_sandbox.o > >> obj-$(CONFIG_VIRTIO_NET) += virtio_net.o > >> obj-$(CONFIG_VIRTIO_BLK) += virtio_blk.o > >> +obj-$(CONFIG_VIRTIO_RNG) += virtio_rng.o > >> diff --git a/drivers/virtio/virtio-uclass.c > >> b/drivers/virtio/virtio-uclass.c > >> index 34397d7..436faa4 100644 > >> --- a/drivers/virtio/virtio-uclass.c > >> +++ b/drivers/virtio/virtio-uclass.c > >> @@ -24,6 +24,7 @@ > >> static const char *const virtio_drv_name[VIRTIO_ID_MAX_NUM] = { > >> [VIRTIO_ID_NET]= VIRTIO_NET_DRV_NAME, > >> [VIRTIO_ID_BLOCK]= VIRTIO_BLK_DRV_NAME, > >> +[VIRTIO_ID_RNG]= VIRTIO_RNG_DRV_NAME, > >> }; > >> > >> int virtio_get_config(struct udevice *vdev, unsigned int offset, > >> diff --git a/drivers/virtio/virtio_rng.c b/drivers/virtio/virtio_rng.c > >> new file mode 100644 > >> index 000..19a0cc1 > >> --- /dev/null > >> +++ b/drivers/virtio/virtio_rng.c > >> @@ -0,0 +1,72 @@ > >> +// SPDX-License-Identifier: GPL-2.0+ > >> +/* > >> + * Copyright (c) 2019, Linaro Limited > >> + */ > >> + > >> +#include > >> +#include > >> +#include > >> +#include > >> +#include > >> +#include > >> + > >> +struct virtio_rng_priv { > >> +struct virtqueue *rng_vq; > >> +}; > >> + > >> +static int virtio_rng_read(struct udevice *dev, void *data, size_t len) > >> +{ > >> +struct virtio_sg sg = { data, len }; > >> +struct virtio_sg *sgs[] = { &sg }; > >> +struct virtio_rng_priv *priv = dev_get_priv(dev); > >> +unsigned int rsize; > >> +int ret; > >> + > >> +ret = virtqueue_add(priv->rng_vq, sgs, 0, 1); > >> +if (ret) > > > > Please, add a debug statement for each error path, e.g. > > > > debug("%s: virtqueue_add() failed\n", __func__) > > > >> +return ret; > >> + > >> +virtqueue_kick(priv->rng_vq); > >> + > >> +while (!virtqueue_get_buf(priv->rng_vq, &rsize)) > >> +; > >> + > >> +return rsize; > > > > The return value is inconsistent with sandbox_rng_read() and > > stm32_rng_read(). Both return 0 on success. > > > > With "return 0;" the driver works fine. > > I retested with > -device virtio-rng-pci,disable-legacy=on,max-bytes=16,period=1000 > > In this case virtqueue_get_buf() only returns a maximum of 16 bytes. All > other bytes of data remain unchanged. If the next call occurs within > 1000 milli-seconds virtqueue_get_buf() blocks until the period is over. > > So either you have to change the definition of the return parameter in > patch 1/8 (and change the other drivers accordingly) or you have to add > a loop to this driver that loops until len random bytes have been > retrieved. > > I would prefer to add a loop in the driver instead of adding a loop in > every consumer. > So I tried putting a loop in the virtio rng driver, but that does not work. I was able to get it working with the loop in the consumer function. So I have changed the return value of the read function in all the drivers to return the number of bytes read, instead of returning 0. I think you will have to change your logic in the rng command patch that you had sent. -sughosh
Re: [PATCH v4 8/8] virtio: rng: Add a random number generator(rng) driver
On 12/24/19 10:39 PM, Heinrich Schuchardt wrote: On 12/17/19 12:52 PM, Sughosh Ganu wrote: Add a driver for the virtio-rng device on the qemu platform. The device uses pci as a transport medium. The driver can be enabled with the following configs CONFIG_VIRTIO CONFIG_DM_RNG CONFIG_VIRTIO_PCI CONFIG_VIRTIO_RNG Signed-off-by: Sughosh Ganu --- drivers/virtio/Kconfig | 6 drivers/virtio/Makefile | 1 + drivers/virtio/virtio-uclass.c | 1 + drivers/virtio/virtio_rng.c | 72 ++ include/virtio.h | 4 ++- 5 files changed, 83 insertions(+), 1 deletion(-) create mode 100644 drivers/virtio/virtio_rng.c diff --git a/drivers/virtio/Kconfig b/drivers/virtio/Kconfig index a9d5fd0..2e3dd3b 100644 --- a/drivers/virtio/Kconfig +++ b/drivers/virtio/Kconfig @@ -59,4 +59,10 @@ config VIRTIO_BLK This is the virtual block driver for virtio. It can be used with QEMU based targets. +config VIRTIO_RNG + bool "virtio rng driver" + depends on VIRTIO + help + This is the virtual random number generator driver. It can be used + with Qemu based targets. endmenu diff --git a/drivers/virtio/Makefile b/drivers/virtio/Makefile index 4579044..dc88809 100644 --- a/drivers/virtio/Makefile +++ b/drivers/virtio/Makefile @@ -9,3 +9,4 @@ obj-$(CONFIG_VIRTIO_PCI) += virtio_pci_legacy.o virtio_pci_modern.o obj-$(CONFIG_VIRTIO_SANDBOX) += virtio_sandbox.o obj-$(CONFIG_VIRTIO_NET) += virtio_net.o obj-$(CONFIG_VIRTIO_BLK) += virtio_blk.o +obj-$(CONFIG_VIRTIO_RNG) += virtio_rng.o diff --git a/drivers/virtio/virtio-uclass.c b/drivers/virtio/virtio-uclass.c index 34397d7..436faa4 100644 --- a/drivers/virtio/virtio-uclass.c +++ b/drivers/virtio/virtio-uclass.c @@ -24,6 +24,7 @@ static const char *const virtio_drv_name[VIRTIO_ID_MAX_NUM] = { [VIRTIO_ID_NET] = VIRTIO_NET_DRV_NAME, [VIRTIO_ID_BLOCK] = VIRTIO_BLK_DRV_NAME, + [VIRTIO_ID_RNG] = VIRTIO_RNG_DRV_NAME, }; int virtio_get_config(struct udevice *vdev, unsigned int offset, diff --git a/drivers/virtio/virtio_rng.c b/drivers/virtio/virtio_rng.c new file mode 100644 index 000..19a0cc1 --- /dev/null +++ b/drivers/virtio/virtio_rng.c @@ -0,0 +1,72 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (c) 2019, Linaro Limited + */ + +#include +#include +#include +#include +#include +#include + +struct virtio_rng_priv { + struct virtqueue *rng_vq; +}; + +static int virtio_rng_read(struct udevice *dev, void *data, size_t len) +{ + struct virtio_sg sg = { data, len }; + struct virtio_sg *sgs[] = { &sg }; + struct virtio_rng_priv *priv = dev_get_priv(dev); + unsigned int rsize; + int ret; + + ret = virtqueue_add(priv->rng_vq, sgs, 0, 1); + if (ret) Please, add a debug statement for each error path, e.g. debug("%s: virtqueue_add() failed\n", __func__) + return ret; + + virtqueue_kick(priv->rng_vq); + + while (!virtqueue_get_buf(priv->rng_vq, &rsize)) + ; + + return rsize; The return value is inconsistent with sandbox_rng_read() and stm32_rng_read(). Both return 0 on success. With "return 0;" the driver works fine. I retested with -device virtio-rng-pci,disable-legacy=on,max-bytes=16,period=1000 In this case virtqueue_get_buf() only returns a maximum of 16 bytes. All other bytes of data remain unchanged. If the next call occurs within 1000 milli-seconds virtqueue_get_buf() blocks until the period is over. So either you have to change the definition of the return parameter in patch 1/8 (and change the other drivers accordingly) or you have to add a loop to this driver that loops until len random bytes have been retrieved. I would prefer to add a loop in the driver instead of adding a loop in every consumer. Best regards Heinrich +} + +static int virtio_rng_bind(struct udevice *dev) +{ + struct virtio_dev_priv *uc_priv = dev_get_uclass_priv(dev->parent); + + /* Indicate what driver features we support */ + virtio_driver_features_init(uc_priv, NULL, 0, NULL, 0); + + return 0; +} + +static int virtio_rng_probe(struct udevice *dev) +{ + struct virtio_rng_priv *priv = dev_get_priv(dev); + int ret; + + ret = virtio_find_vqs(dev, 1, &priv->rng_vq); + if (ret < 0) Add a debug statement here, please, e.g. debug("%s: virtio_find_vqs() failed\n", __func__) Best regards Heinrich + return ret; + + return 0; +} + +static const struct dm_rng_ops virtio_rng_ops = { + .read = virtio_rng_read, +}; + +U_BOOT_DRIVER(virtio_rng) = { + .name = VIRTIO_RNG_DRV_NAME, + .id = UCLASS_RNG, + .bind = virtio_rng_bind, + .probe = virtio_rng_probe, + .remove = virtio_reset, + .ops = &virtio_rng_ops, + .priv_auto_alloc_size = sizeof(struct virtio_rng_priv), + .flags = DM_FLAG_ACTIVE_DMA, +}; diff --git a/include/virtio.h b/include/virtio.h index 654fdf1..561dcc3 100644 --- a/
Re: [PATCH v4 8/8] virtio: rng: Add a random number generator(rng) driver
On 12/17/19 12:52 PM, Sughosh Ganu wrote: Add a driver for the virtio-rng device on the qemu platform. The device uses pci as a transport medium. The driver can be enabled with the following configs CONFIG_VIRTIO CONFIG_DM_RNG CONFIG_VIRTIO_PCI CONFIG_VIRTIO_RNG Signed-off-by: Sughosh Ganu --- drivers/virtio/Kconfig | 6 drivers/virtio/Makefile| 1 + drivers/virtio/virtio-uclass.c | 1 + drivers/virtio/virtio_rng.c| 72 ++ include/virtio.h | 4 ++- 5 files changed, 83 insertions(+), 1 deletion(-) create mode 100644 drivers/virtio/virtio_rng.c diff --git a/drivers/virtio/Kconfig b/drivers/virtio/Kconfig index a9d5fd0..2e3dd3b 100644 --- a/drivers/virtio/Kconfig +++ b/drivers/virtio/Kconfig @@ -59,4 +59,10 @@ config VIRTIO_BLK This is the virtual block driver for virtio. It can be used with QEMU based targets. +config VIRTIO_RNG + bool "virtio rng driver" + depends on VIRTIO + help + This is the virtual random number generator driver. It can be used +with Qemu based targets. endmenu diff --git a/drivers/virtio/Makefile b/drivers/virtio/Makefile index 4579044..dc88809 100644 --- a/drivers/virtio/Makefile +++ b/drivers/virtio/Makefile @@ -9,3 +9,4 @@ obj-$(CONFIG_VIRTIO_PCI) += virtio_pci_legacy.o virtio_pci_modern.o obj-$(CONFIG_VIRTIO_SANDBOX) += virtio_sandbox.o obj-$(CONFIG_VIRTIO_NET) += virtio_net.o obj-$(CONFIG_VIRTIO_BLK) += virtio_blk.o +obj-$(CONFIG_VIRTIO_RNG) += virtio_rng.o diff --git a/drivers/virtio/virtio-uclass.c b/drivers/virtio/virtio-uclass.c index 34397d7..436faa4 100644 --- a/drivers/virtio/virtio-uclass.c +++ b/drivers/virtio/virtio-uclass.c @@ -24,6 +24,7 @@ static const char *const virtio_drv_name[VIRTIO_ID_MAX_NUM] = { [VIRTIO_ID_NET] = VIRTIO_NET_DRV_NAME, [VIRTIO_ID_BLOCK] = VIRTIO_BLK_DRV_NAME, + [VIRTIO_ID_RNG] = VIRTIO_RNG_DRV_NAME, }; int virtio_get_config(struct udevice *vdev, unsigned int offset, diff --git a/drivers/virtio/virtio_rng.c b/drivers/virtio/virtio_rng.c new file mode 100644 index 000..19a0cc1 --- /dev/null +++ b/drivers/virtio/virtio_rng.c @@ -0,0 +1,72 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (c) 2019, Linaro Limited + */ + +#include +#include +#include +#include +#include +#include + +struct virtio_rng_priv { + struct virtqueue *rng_vq; +}; + +static int virtio_rng_read(struct udevice *dev, void *data, size_t len) +{ + struct virtio_sg sg = { data, len }; + struct virtio_sg *sgs[] = { &sg }; + struct virtio_rng_priv *priv = dev_get_priv(dev); + unsigned int rsize; + int ret; + + ret = virtqueue_add(priv->rng_vq, sgs, 0, 1); + if (ret) Please, add a debug statement for each error path, e.g. debug("%s: virtqueue_add() failed\n", __func__) + return ret; + + virtqueue_kick(priv->rng_vq); + + while (!virtqueue_get_buf(priv->rng_vq, &rsize)) + ; + + return rsize; The return value is inconsistent with sandbox_rng_read() and stm32_rng_read(). Both return 0 on success. With "return 0;" the driver works fine. +} + +static int virtio_rng_bind(struct udevice *dev) +{ + struct virtio_dev_priv *uc_priv = dev_get_uclass_priv(dev->parent); + + /* Indicate what driver features we support */ + virtio_driver_features_init(uc_priv, NULL, 0, NULL, 0); + + return 0; +} + +static int virtio_rng_probe(struct udevice *dev) +{ + struct virtio_rng_priv *priv = dev_get_priv(dev); + int ret; + + ret = virtio_find_vqs(dev, 1, &priv->rng_vq); + if (ret < 0) Add a debug statement here, please, e.g. debug("%s: virtio_find_vqs() failed\n", __func__) Best regards Heinrich + return ret; + + return 0; +} + +static const struct dm_rng_ops virtio_rng_ops = { + .read = virtio_rng_read, +}; + +U_BOOT_DRIVER(virtio_rng) = { + .name = VIRTIO_RNG_DRV_NAME, + .id = UCLASS_RNG, + .bind = virtio_rng_bind, + .probe = virtio_rng_probe, + .remove = virtio_reset, + .ops= &virtio_rng_ops, + .priv_auto_alloc_size = sizeof(struct virtio_rng_priv), + .flags = DM_FLAG_ACTIVE_DMA, +}; diff --git a/include/virtio.h b/include/virtio.h index 654fdf1..561dcc3 100644 --- a/include/virtio.h +++ b/include/virtio.h @@ -22,10 +22,12 @@ #define VIRTIO_ID_NET 1 /* virtio net */ #define VIRTIO_ID_BLOCK 2 /* virtio block */ -#define VIRTIO_ID_MAX_NUM 3 +#define VIRTIO_ID_RNG 4 /* virtio rng */ +#define VIRTIO_ID_MAX_NUM 5 #define VIRTIO_NET_DRV_NAME "virtio-net" #define VIRTIO_BLK_DRV_NAME "virtio-blk" +#define VIRTIO_RNG_DRV_NAME"virtio-rng" /* Status byte for guest to report progress, and synchronize features */
[PATCH v4 8/8] virtio: rng: Add a random number generator(rng) driver
Add a driver for the virtio-rng device on the qemu platform. The device uses pci as a transport medium. The driver can be enabled with the following configs CONFIG_VIRTIO CONFIG_DM_RNG CONFIG_VIRTIO_PCI CONFIG_VIRTIO_RNG Signed-off-by: Sughosh Ganu --- drivers/virtio/Kconfig | 6 drivers/virtio/Makefile| 1 + drivers/virtio/virtio-uclass.c | 1 + drivers/virtio/virtio_rng.c| 72 ++ include/virtio.h | 4 ++- 5 files changed, 83 insertions(+), 1 deletion(-) create mode 100644 drivers/virtio/virtio_rng.c diff --git a/drivers/virtio/Kconfig b/drivers/virtio/Kconfig index a9d5fd0..2e3dd3b 100644 --- a/drivers/virtio/Kconfig +++ b/drivers/virtio/Kconfig @@ -59,4 +59,10 @@ config VIRTIO_BLK This is the virtual block driver for virtio. It can be used with QEMU based targets. +config VIRTIO_RNG + bool "virtio rng driver" + depends on VIRTIO + help + This is the virtual random number generator driver. It can be used +with Qemu based targets. endmenu diff --git a/drivers/virtio/Makefile b/drivers/virtio/Makefile index 4579044..dc88809 100644 --- a/drivers/virtio/Makefile +++ b/drivers/virtio/Makefile @@ -9,3 +9,4 @@ obj-$(CONFIG_VIRTIO_PCI) += virtio_pci_legacy.o virtio_pci_modern.o obj-$(CONFIG_VIRTIO_SANDBOX) += virtio_sandbox.o obj-$(CONFIG_VIRTIO_NET) += virtio_net.o obj-$(CONFIG_VIRTIO_BLK) += virtio_blk.o +obj-$(CONFIG_VIRTIO_RNG) += virtio_rng.o diff --git a/drivers/virtio/virtio-uclass.c b/drivers/virtio/virtio-uclass.c index 34397d7..436faa4 100644 --- a/drivers/virtio/virtio-uclass.c +++ b/drivers/virtio/virtio-uclass.c @@ -24,6 +24,7 @@ static const char *const virtio_drv_name[VIRTIO_ID_MAX_NUM] = { [VIRTIO_ID_NET] = VIRTIO_NET_DRV_NAME, [VIRTIO_ID_BLOCK] = VIRTIO_BLK_DRV_NAME, + [VIRTIO_ID_RNG] = VIRTIO_RNG_DRV_NAME, }; int virtio_get_config(struct udevice *vdev, unsigned int offset, diff --git a/drivers/virtio/virtio_rng.c b/drivers/virtio/virtio_rng.c new file mode 100644 index 000..19a0cc1 --- /dev/null +++ b/drivers/virtio/virtio_rng.c @@ -0,0 +1,72 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (c) 2019, Linaro Limited + */ + +#include +#include +#include +#include +#include +#include + +struct virtio_rng_priv { + struct virtqueue *rng_vq; +}; + +static int virtio_rng_read(struct udevice *dev, void *data, size_t len) +{ + struct virtio_sg sg = { data, len }; + struct virtio_sg *sgs[] = { &sg }; + struct virtio_rng_priv *priv = dev_get_priv(dev); + unsigned int rsize; + int ret; + + ret = virtqueue_add(priv->rng_vq, sgs, 0, 1); + if (ret) + return ret; + + virtqueue_kick(priv->rng_vq); + + while (!virtqueue_get_buf(priv->rng_vq, &rsize)) + ; + + return rsize; +} + +static int virtio_rng_bind(struct udevice *dev) +{ + struct virtio_dev_priv *uc_priv = dev_get_uclass_priv(dev->parent); + + /* Indicate what driver features we support */ + virtio_driver_features_init(uc_priv, NULL, 0, NULL, 0); + + return 0; +} + +static int virtio_rng_probe(struct udevice *dev) +{ + struct virtio_rng_priv *priv = dev_get_priv(dev); + int ret; + + ret = virtio_find_vqs(dev, 1, &priv->rng_vq); + if (ret < 0) + return ret; + + return 0; +} + +static const struct dm_rng_ops virtio_rng_ops = { + .read = virtio_rng_read, +}; + +U_BOOT_DRIVER(virtio_rng) = { + .name = VIRTIO_RNG_DRV_NAME, + .id = UCLASS_RNG, + .bind = virtio_rng_bind, + .probe = virtio_rng_probe, + .remove = virtio_reset, + .ops= &virtio_rng_ops, + .priv_auto_alloc_size = sizeof(struct virtio_rng_priv), + .flags = DM_FLAG_ACTIVE_DMA, +}; diff --git a/include/virtio.h b/include/virtio.h index 654fdf1..561dcc3 100644 --- a/include/virtio.h +++ b/include/virtio.h @@ -22,10 +22,12 @@ #define VIRTIO_ID_NET 1 /* virtio net */ #define VIRTIO_ID_BLOCK2 /* virtio block */ -#define VIRTIO_ID_MAX_NUM 3 +#define VIRTIO_ID_RNG 4 /* virtio rng */ +#define VIRTIO_ID_MAX_NUM 5 #define VIRTIO_NET_DRV_NAME"virtio-net" #define VIRTIO_BLK_DRV_NAME"virtio-blk" +#define VIRTIO_RNG_DRV_NAME"virtio-rng" /* Status byte for guest to report progress, and synchronize features */ -- 2.7.4