Re: [PATCH v5 02/23] FWU: Add FWU metadata structure and driver for accessing metadata

[Sughosh Ganu <sughosh.ganu@linaro.org>]

hi Etienne,

On Tue, 21 Jun 2022 at 16:24, Etienne Carriere
<etienne.carriere@linaro.org> wrote:
>
> Hello Sughosh,
>
>
>
> On Thu, 9 Jun 2022 at 14:30, Sughosh Ganu <sughosh.ganu@linaro.org> wrote:
> >
> > In the FWU Multi Bank Update feature, the information about the
> > updatable images is stored as part of the metadata, which is stored on
> > a dedicated partition. Add the metadata structure, and a driver model
> > uclass which provides functions to access the metadata. These are
> > generic API's, and implementations can be added based on parameters
> > like how the metadata partition is accessed and what type of storage
> > device houses the metadata.
> >
> > Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org>
> > ---
> >  drivers/Kconfig                      |   2 +
> >  drivers/Makefile                     |   1 +
> >  drivers/fwu-mdata/Kconfig            |   7 +
> >  drivers/fwu-mdata/Makefile           |   6 +
> >  drivers/fwu-mdata/fwu-mdata-uclass.c | 459 +++++++++++++++++++++++++++
> >  include/dm/uclass-id.h               |   1 +
> >  include/fwu.h                        |  49 +++
> >  include/fwu_mdata.h                  |  67 ++++
> >  8 files changed, 592 insertions(+)
> >  create mode 100644 drivers/fwu-mdata/Kconfig
> >  create mode 100644 drivers/fwu-mdata/Makefile
> >  create mode 100644 drivers/fwu-mdata/fwu-mdata-uclass.c
> >  create mode 100644 include/fwu.h
> >  create mode 100644 include/fwu_mdata.h
> >

<snip>

> > diff --git a/drivers/fwu-mdata/fwu-mdata-uclass.c b/drivers/fwu-mdata/fwu-mdata-uclass.c
> > new file mode 100644
> > index 0000000000..1530ceb01d
> > --- /dev/null
> > +++ b/drivers/fwu-mdata/fwu-mdata-uclass.c
> > @@ -0,0 +1,459 @@
> > +// SPDX-License-Identifier: GPL-2.0+
> > +/*
> > + * Copyright (c) 2022, Linaro Limited
> > + */
> > +
> > +#include <common.h>
> > +#include <dm.h>
> > +#include <efi_loader.h>
> > +#include <fwu.h>
> > +#include <fwu_mdata.h>
> > +#include <log.h>
> > +#include <malloc.h>
> > +
> > +#include <linux/errno.h>
> > +#include <linux/types.h>
> > +#include <u-boot/crc.h>
> > +
> > +#define IMAGE_ACCEPT_SET       BIT(0)
> > +#define IMAGE_ACCEPT_CLEAR     BIT(1)
> > +
> > +static int fwu_get_dev_ops(struct udevice **dev,
> > +                          const struct fwu_mdata_ops **ops)
> > +{
> > +       int ret;
> > +
> > +       ret = uclass_get_device(UCLASS_FWU_MDATA, 0, dev);
> > +       if (ret) {
> > +               log_debug("Cannot find fwu device\n");
> > +               return ret;
> > +       }
> > +
> > +       if ((*ops = device_get_ops(*dev)) == NULL) {
> > +               log_debug("Cannot get fwu device ops\n");
> > +               return -ENOSYS;
> > +       }
> > +
> > +       return 0;
> > +}
> > +
> > +/**
> > + * fwu_verify_mdata() - Verify the FWU metadata
> > + * @mdata: FWU metadata structure
> > + * @pri_part: FWU metadata partition is primary or secondary
> > + *
> > + * Verify the FWU metadata by computing the CRC32 for the metadata
> > + * structure and comparing it against the CRC32 value stored as part
> > + * of the structure.
> > + *
> > + * Return: 0 if OK, -ve on error
> > + *
> > + */
> > +int fwu_verify_mdata(struct fwu_mdata *mdata, bool pri_part)
> > +{
> > +       u32 calc_crc32;
> > +       void *buf;
> > +
> > +       buf = &mdata->version;
> > +       calc_crc32 = crc32(0, buf, sizeof(*mdata) - sizeof(u32));
> > +
> > +       if (calc_crc32 != mdata->crc32) {
> > +               log_err("crc32 check failed for %s FWU metadata partition\n",
> > +                       pri_part ? "primary" : "secondary");
> > +               return -1;
> > +       }
> > +
> > +       return 0;
> > +}
> > +
> > +/**
> > + * fwu_get_active_index() - Get active_index from the FWU metadata
> > + * @active_idx: active_index value to be read
> > + *
> > + * Read the active_index field from the FWU metadata and place it in
> > + * the variable pointed to be the function argument.
> > + *
> > + * Return: 0 if OK, -ve on error
> > + *
> > + */
> > +int fwu_get_active_index(u32 *active_idx)
> > +{
> > +       int ret;
> > +       struct fwu_mdata *mdata = NULL;
> > +
> > +       ret = fwu_get_mdata(&mdata);
> > +       if (ret < 0) {
> > +               log_err("Unable to get valid FWU metadata\n");
> > +               goto out;
> > +       }
> > +
> > +       /*
> > +        * Found the FWU metadata partition, now read the active_index
> > +        * value
> > +        */
> > +       *active_idx = mdata->active_index;
> > +       if (*active_idx > CONFIG_FWU_NUM_BANKS - 1) {
> > +               log_err("Active index value read is incorrect\n");
> > +               ret = -EINVAL;
> > +       }
> > +
> > +out:
> > +       free(mdata);
> > +
> > +       return ret;
> > +}
> > +
> > +/**
> > + * fwu_update_active_index() - Update active_index from the FWU metadata
> > + * @active_idx: active_index value to be updated
> > + *
> > + * Update the active_index field in the FWU metadata
> > + *
> > + * Return: 0 if OK, -ve on error
> > + *
> > + */
> > +int fwu_update_active_index(u32 active_idx)
> > +{
> > +       int ret;
> > +       struct fwu_mdata *mdata = NULL;
> > +
> > +       if (active_idx > CONFIG_FWU_NUM_BANKS - 1) {
> > +               log_err("Active index value to be updated is incorrect\n");
> > +               return -1;
> > +       }
> > +
> > +       ret = fwu_get_mdata(&mdata);
> > +       if (ret < 0) {
> > +               log_err("Unable to get valid FWU metadata\n");
> > +               goto out;
> > +       }
> > +
> > +       /*
> > +        * Update the active index and previous_active_index fields
> > +        * in the FWU metadata
> > +        */
> > +       mdata->previous_active_index = mdata->active_index;
> > +       mdata->active_index = active_idx;
> > +
> > +       /*
> > +        * Now write this updated FWU metadata to both the
> > +        * FWU metadata partitions
> > +        */
> > +       ret = fwu_update_mdata(mdata);
> > +       if (ret < 0) {> +               log_err("Failed to update FWU metadata partitions\n");
> > +               ret = -EIO;
> > +       }
> > +
> > +out:
> > +       free(mdata);
> > +
> > +       return ret;
> > +}
> > +
> > +/**
> > + * fwu_get_image_alt_num() - Get the dfu alt number to be used for capsule update
> > + * @image_type_id: pointer to the image guid as passed in the capsule
> > + * @update_bank: Bank to which the update is to be made
> > + * @alt_num: The alt_num for the image
> > + *
> > + * Based on the guid value passed in the capsule, along with the bank to which the
> > + * image needs to be updated, get the dfu alt number which will be used for the
> > + * capsule update
> > + *
> > + * Return: 0 if OK, -ve on error
> > + *
> > + */
> > +int fwu_get_image_alt_num(efi_guid_t *image_type_id, u32 update_bank,
> > +                         int *alt_num)
> > +{
> > +       int ret, i;
> > +       efi_guid_t *image_guid;
> > +       struct udevice *dev = NULL;
> > +       struct fwu_mdata *mdata = NULL;
> > +       struct fwu_image_entry *img_entry;
> > +       const struct fwu_mdata_ops *ops = NULL;
> > +       struct fwu_image_bank_info *img_bank_info;
> > +
> > +       ret = fwu_get_dev_ops(&dev, &ops);
> > +       if (ret)
> > +               return ret;
> > +
> > +       ret = fwu_get_mdata(&mdata);
> > +       if (ret) {
> > +               log_err("Unable to get valid FWU metadata\n");
> > +               goto out;
> > +       }
> > +
> > +       /*
> > +        * The FWU metadata has been read. Now get the image_uuid for the
> > +        * image with the update_bank.
> > +        */
> > +       for (i = 0; i < CONFIG_FWU_NUM_IMAGES_PER_BANK; i++) {
> > +               if (!guidcmp(image_type_id,
> > +                            &mdata->img_entry[i].image_type_uuid)) {
> > +                       img_entry = &mdata->img_entry[i];
> > +                       img_bank_info = &img_entry->img_bank_info[update_bank];
> > +                       image_guid = &img_bank_info->image_uuid;
> > +                       ret = fwu_plat_get_alt_num(dev_get_priv(dev),
> > +                                                  image_guid, alt_num);
> > +                       break;
> > +               }
> > +       }
> > +
> > +       if (i == CONFIG_FWU_NUM_IMAGES_PER_BANK) {
> > +               log_err("Partition with the image type %pUs not found\n",
> > +                       image_type_id);
> > +               ret = -EINVAL;
> > +               goto out;
> > +       }
> > +
> > +       if (!ret) {
> > +               log_debug("alt_num %d for partition %pUs\n",
> > +                         *alt_num, &image_guid);
>
> s/&image_guid/image_guid/
> Ditto in trace below.

Will fix both.

>
> > +       } else {
> > +               log_err("alt_num not found for partition with GUID %pUs\n",
> > +                       &image_guid);
> > +               ret = -EINVAL;
> > +       }
> > +
> > +out:
> > +       free(mdata);
> > +
> > +       return ret;
> > +}
> > +
> > +/**
> > + * fwu_mdata_check() - Check if the FWU metadata is valid
> > + *
> > + * Validate both copies of the FWU metadata. If one of the copies
> > + * has gone bad, restore it from the other bad copy.
> > + *
> > + * Return: 0 if OK, -ve on error
> > + *
> > + */
> > +int fwu_mdata_check(void)
> > +{
> > +       int ret;
> > +       struct udevice *dev = NULL;
> > +       const struct fwu_mdata_ops *ops = NULL;
> > +
> > +       ret = fwu_get_dev_ops(&dev, &ops);
> > +       if (ret)
> > +               return ret;
> > +
> > +       if (!ops->mdata_check) {
> > +               log_err("mdata_check() method not defined\n");
> > +               return -ENOSYS;
> > +       }
> > +
> > +       return ops->mdata_check(dev);
> > +}
> > +
> > +/**
> > + * fwu_revert_boot_index() - Revert the active index in the FWU metadata
> > + *
> > + * Revert the active_index value in the FWU metadata, by swapping the values
> > + * of active_index and previous_active_index in both copies of the
> > + * FWU metadata.
> > + *
> > + * Return: 0 if OK, -ve on error
> > + *
> > + */
> > +int fwu_revert_boot_index(void)
> > +{
> > +       int ret;
> > +       u32 cur_active_index;
> > +       struct fwu_mdata *mdata = NULL;
> > +
> > +       ret = fwu_get_mdata(&mdata);
> > +       if (ret < 0) {
> > +               log_err("Unable to get valid FWU metadata\n");
> > +               goto out;
> > +       }
> > +
> > +       /*
> > +        * Swap the active index and previous_active_index fields
> > +        * in the FWU metadata
> > +        */
> > +       cur_active_index = mdata->active_index;
> > +       mdata->active_index = mdata->previous_active_index;
> > +       mdata->previous_active_index = cur_active_index;
> > +
> > +       /*
> > +        * Now write this updated FWU metadata to both the
> > +        * FWU metadata partitions
> > +        */
> > +       ret = fwu_update_mdata(mdata);
> > +       if (ret < 0) {
> > +               log_err("Failed to update FWU metadata partitions\n");
> > +               ret = -EIO;
> > +       }
> > +
> > +out:
> > +       free(mdata);
> > +
> > +       return ret;
> > +}
> > +
> > +/**
> > + * fwu_set_clear_image_accept() - Set or Clear the Acceptance bit for the image
> > + * @img_type_id: Guid of the image type for which the accepted bit is to be
> > + *               set or cleared
> > + * @bank: Bank of which the image's Accept bit is to be set or cleared
> > + * @action: Action which specifies whether image's Accept bit is to be set or
> > + *          cleared
> > + *
> > + * Set/Clear the accepted bit for the image specified by the img_guid parameter.
> > + * This indicates acceptance or rejection of image for subsequent boots by some
> > + * governing component like OS(or firmware).
> > + *
> > + * Return: 0 if OK, -ve on error
> > + *
> > + */
> > +static int fwu_set_clear_image_accept(efi_guid_t *img_type_id,
> > +                                     u32 bank, u8 action)
> > +{
> > +       int ret, i;
> > +       u32 nimages;
> > +       struct fwu_mdata *mdata = NULL;
> > +       struct fwu_image_entry *img_entry;
> > +       struct fwu_image_bank_info *img_bank_info;
> > +
> > +       ret = fwu_get_mdata(&mdata);
> > +       if (ret < 0) {
> > +               log_err("Unable to get valid FWU metadata\n");
> > +               goto out;
> > +       }
> > +
> > +       nimages = CONFIG_FWU_NUM_IMAGES_PER_BANK;
> > +       img_entry = &mdata->img_entry[0];
> > +       for (i = 0; i < nimages; i++) {
> > +               if (!guidcmp(&img_entry[i].image_type_uuid, img_type_id)) {
> > +                       img_bank_info = &img_entry[i].img_bank_info[bank];
> > +                       if (action == IMAGE_ACCEPT_SET)
> > +                               img_bank_info->accepted |= FWU_IMAGE_ACCEPTED;
> > +                       else
> > +                               img_bank_info->accepted = 0;
> > +
> > +                       ret = fwu_update_mdata(mdata);
> > +                       goto out;
> > +               }
> > +       }
> > +
> > +       /* Image not found */
> > +       ret = -EINVAL;
> > +
> > +out:
> > +       free(mdata);
> > +
> > +       return ret;
> > +}
> > +
> > +/**
> > + * fwu_accept_image() - Set the Acceptance bit for the image
> > + * @img_type_id: Guid of the image type for which the accepted bit is to be
> > + *               cleared
> > + * @bank: Bank of which the image's Accept bit is to be set
> > + *
> > + * Set the accepted bit for the image specified by the img_guid parameter. This
> > + * indicates acceptance of image for subsequent boots by some governing component
> > + * like OS(or firmware).
> > + *
> > + * Return: 0 if OK, -ve on error
> > + *
> > + */
> > +int fwu_accept_image(efi_guid_t *img_type_id, u32 bank)
> > +{
> > +       return fwu_set_clear_image_accept(img_type_id, bank,
> > +                                         IMAGE_ACCEPT_SET);
> > +}
> > +
> > +/**
> > + * fwu_clear_accept_image() - Clear the Acceptance bit for the image
> > + * @img_type_id: Guid of the image type for which the accepted bit is to be
> > + *               cleared
> > + * @bank: Bank of which the image's Accept bit is to be cleared
> > + *
> > + * Clear the accepted bit for the image type specified by the img_type_id parameter.
> > + * This function is called after the image has been updated. The accepted bit is
> > + * cleared to be set subsequently after passing the image acceptance criteria, by
> > + * either the OS(or firmware)
> > + *
> > + * Return: 0 if OK, -ve on error
> > + *
> > + */
> > +int fwu_clear_accept_image(efi_guid_t *img_type_id, u32 bank)
> > +{
> > +       return fwu_set_clear_image_accept(img_type_id, bank,
> > +                                         IMAGE_ACCEPT_CLEAR);
> > +}
> > +
> > +/**
> > + * fwu_get_mdata() - Get a FWU metadata copy
> > + * @mdata: Copy of the FWU metadata
> > + *
> > + * Get a valid copy of the FWU metadata.
> > + *
> > + * Return: 0 if OK, -ve on error
> > + *
> > + */
> > +int fwu_get_mdata(struct fwu_mdata **mdata)
>
> Is there a real need for this function to allocate an instance of struct mdata.
> I think it would be clearer if it was the caller's responsibility to
> allocate/free the structure.
>
> Or maybe rename this function fwu_alloc_and_copy_mdata() to highlight
> that the function gives an allocated copy of the data.

I guess I can put a comment in the function description saying that
the function is responsible for the allocation of the metadata
structure.

> One should be careful when calling these API functions as some act on
> a local copy (retrieved from fw_get_mdata()) while other functions
> modify straight fwu-mdata in the storage media.

Did you find any function which is modifying the metadata on the
storage device directly. The API fwu_update_mdata() is supposed to be
doing that. If you have come across any function which is directly
modifying the metadata on the storage media, please let me know and I
will fix it.

-sughosh

>
> Br,
> etienne
>
>
>
> > +{
> > +       int ret;
> > +       struct udevice *dev = NULL;
> > +       const struct fwu_mdata_ops *ops = NULL;
> > +
> > +       ret = fwu_get_dev_ops(&dev, &ops);
> > +       if (ret)
> > +               return ret;
> > +
> > +       if (!ops->get_mdata) {
> > +               log_err("get_mdata() method not defined\n");
> > +               return -ENOSYS;
> > +       }
> > +
> > +       return ops->get_mdata(dev, mdata);
> > +}
> > +
> > +/**
> > + * fwu_update_mdata() - Update the FWU metadata
> > + * @mdata: Copy of the FWU metadata
> > + *
> > + * Update the FWU metadata structure by writing to the
> > + * FWU metadata partitions.
> > + *
> > + * Return: 0 if OK, -ve on error
> > + *
> > + */
> > +int fwu_update_mdata(struct fwu_mdata *mdata)
> > +{
> > +       int ret;
> > +       void *buf;
> > +       struct udevice *dev = NULL;
> > +       const struct fwu_mdata_ops *ops = NULL;
> > +
> > +       ret = fwu_get_dev_ops(&dev, &ops);
> > +       if (ret)
> > +               return ret;
> > +
> > +       if (!ops->update_mdata) {
> > +               log_err("get_mdata() method not defined\n");
> > +               return -ENOSYS;
> > +       }
> > +
> > +       /*
> > +        * Calculate the crc32 for the updated FWU metadata
> > +        * and put the updated value in the FWU metadata crc32
> > +        * field
> > +        */
> > +       buf = &mdata->version;
> > +       mdata->crc32 = crc32(0, buf, sizeof(*mdata) - sizeof(u32));
> > +
> > +       return ops->update_mdata(dev, mdata);
> > +}
> > +
> > +UCLASS_DRIVER(fwu_mdata) = {
> > +       .id             = UCLASS_FWU_MDATA,
> > +       .name           = "fwu-mdata",
> > +};
> > diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h
> > index 3ba69ad9a0..7da719c048 100644
> > --- a/include/dm/uclass-id.h
> > +++ b/include/dm/uclass-id.h
> > @@ -57,6 +57,7 @@ enum uclass_id {
> >         UCLASS_ETH_PHY,         /* Ethernet PHY device */
> >         UCLASS_FIRMWARE,        /* Firmware */
> >         UCLASS_FS_FIRMWARE_LOADER,              /* Generic loader */
> > +       UCLASS_FWU_MDATA,       /* FWU Metadata Access */
> >         UCLASS_GPIO,            /* Bank of general-purpose I/O pins */
> >         UCLASS_HASH,            /* Hash device */
> >         UCLASS_HWSPINLOCK,      /* Hardware semaphores */
> > diff --git a/include/fwu.h b/include/fwu.h
> > new file mode 100644
> > index 0000000000..f9e44e7b39
> > --- /dev/null
> > +++ b/include/fwu.h
> > @@ -0,0 +1,49 @@
> > +/* SPDX-License-Identifier: GPL-2.0+ */
> > +/*
> > + * Copyright (c) 2022, Linaro Limited
> > + */
> > +
> > +#if !defined _FWU_H_
> > +#define _FWU_H_
> > +
> > +#include <blk.h>
> > +#include <efi.h>
> > +
> > +#include <linux/types.h>
> > +
> > +struct fwu_mdata;
> > +struct udevice;
> > +
> > +/**
> > + * @mdata_check: check the validity of the FWU metadata partitions
> > + * @get_mdata() - Get a FWU metadata copy
> > + * @update_mdata() - Update the FWU metadata copy
> > + */
> > +struct fwu_mdata_ops {
> > +       int (*mdata_check)(struct udevice *dev);
> > +
> > +       int (*get_mdata)(struct udevice *dev, struct fwu_mdata **mdata);
> > +
> > +       int (*update_mdata)(struct udevice *dev, struct fwu_mdata *mdata);
> > +};
> > +
> > +#define FWU_MDATA_VERSION      0x1
> > +
> > +#define FWU_MDATA_GUID \
> > +       EFI_GUID(0x8a7a84a0, 0x8387, 0x40f6, 0xab, 0x41, \
> > +                0xa8, 0xb9, 0xa5, 0xa6, 0x0d, 0x23)
> > +
> > +int fwu_get_mdata(struct fwu_mdata **mdata);
> > +int fwu_update_mdata(struct fwu_mdata *mdata);
> > +int fwu_get_active_index(u32 *active_idx);
> > +int fwu_update_active_index(u32 active_idx);
> > +int fwu_get_image_alt_num(efi_guid_t *image_type_id, u32 update_bank,
> > +                         int *alt_num);
> > +int fwu_mdata_check(void);
> > +int fwu_revert_boot_index(void);
> > +int fwu_accept_image(efi_guid_t *img_type_id, u32 bank);
> > +int fwu_clear_accept_image(efi_guid_t *img_type_id, u32 bank);
> > +
> > +int fwu_plat_get_alt_num(struct udevice *dev, efi_guid_t *image_guid,
> > +                        int *alt_num);
> > +#endif /* _FWU_H_ */
> > diff --git a/include/fwu_mdata.h b/include/fwu_mdata.h
> > new file mode 100644
> > index 0000000000..701efbba03
> > --- /dev/null
> > +++ b/include/fwu_mdata.h
> > @@ -0,0 +1,67 @@
> > +/* SPDX-License-Identifier: GPL-2.0+ */
> > +/*
> > + * Copyright (c) 2022, Linaro Limited
> > + */
> > +
> > +#if !defined _FWU_MDATA_H_
> > +#define _FWU_MDATA_H_
> > +
> > +#include <efi.h>
> > +
> > +/**
> > + * struct fwu_image_bank_info - firmware image information
> > + * @image_uuid: Guid value of the image in this bank
> > + * @accepted: Acceptance status of the image
> > + * @reserved: Reserved
> > + *
> > + * The structure contains image specific fields which are
> > + * used to identify the image and to specify the image's
> > + * acceptance status
> > + */
> > +struct fwu_image_bank_info {
> > +       efi_guid_t  image_uuid;
> > +       uint32_t accepted;
> > +       uint32_t reserved;
> > +} __attribute__((__packed__));
> > +
> > +/**
> > + * struct fwu_image_entry - information for a particular type of image
> > + * @image_type_uuid: Guid value for identifying the image type
> > + * @location_uuid: Guid of the storage volume where the image is located
> > + * @img_bank_info: Array containing properties of images
> > + *
> > + * This structure contains information on various types of updatable
> > + * firmware images. Each image type then contains an array of image
> > + * information per bank.
> > + */
> > +struct fwu_image_entry {
> > +       efi_guid_t image_type_uuid;
> > +       efi_guid_t location_uuid;
> > +       struct fwu_image_bank_info img_bank_info[CONFIG_FWU_NUM_BANKS];
> > +} __attribute__((__packed__));
> > +
> > +/**
> > + * struct fwu_mdata - FWU metadata structure for multi-bank updates
> > + * @crc32: crc32 value for the FWU metadata
> > + * @version: FWU metadata version
> > + * @active_index: Index of the bank currently used for booting images
> > + * @previous_active_inde: Index of the bank used before the current bank
> > + *                        being used for booting
> > + * @img_entry: Array of information on various firmware images that can
> > + *             be updated
> > + *
> > + * This structure is used to store all the needed information for performing
> > + * multi bank updates on the platform. This contains info on the bank being
> > + * used to boot along with the information needed for identification of
> > + * individual images
> > + */
> > +struct fwu_mdata {
> > +       uint32_t crc32;
> > +       uint32_t version;
> > +       uint32_t active_index;
> > +       uint32_t previous_active_index;
> > +
> > +       struct fwu_image_entry img_entry[CONFIG_FWU_NUM_IMAGES_PER_BANK];
> > +} __attribute__((__packed__));
> > +
> > +#endif /* _FWU_MDATA_H_ */
> > --
> > 2.25.1
> >