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| author | Jani Nikula <jani.nikula@intel.com> | 2024-08-01 13:06:09 +0300 |
|---|---|---|
| committer | Jani Nikula <jani.nikula@intel.com> | 2024-08-01 13:06:09 +0300 |
| commit | 3663e2c4bc45fcdc71931fcbfcbfbf9b71f55c83 (patch) | |
| tree | 3927fa90c7faa89131fcf2e789ca9de97a65dc5f /include/vdso/getrandom.h | |
| parent | 688c43dd6ca9e0cd0568868aefca5b041695c3f4 (diff) | |
| parent | 8400291e289ee6b2bf9779ff1c83a291501f017b (diff) | |
| download | lwn-3663e2c4bc45fcdc71931fcbfcbfbf9b71f55c83.tar.gz lwn-3663e2c4bc45fcdc71931fcbfcbfbf9b71f55c83.zip | |
Merge drm/drm-next into drm-intel-next
Sync with v6.11-rc1 in general, and specifically get the new
BACKLIGHT_POWER_ constants for power states.
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Diffstat (limited to 'include/vdso/getrandom.h')
| -rw-r--r-- | include/vdso/getrandom.h | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/include/vdso/getrandom.h b/include/vdso/getrandom.h new file mode 100644 index 000000000000..a8b7c14b0ae0 --- /dev/null +++ b/include/vdso/getrandom.h @@ -0,0 +1,46 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2022-2024 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved. + */ + +#ifndef _VDSO_GETRANDOM_H +#define _VDSO_GETRANDOM_H + +#include <linux/types.h> + +#define CHACHA_KEY_SIZE 32 +#define CHACHA_BLOCK_SIZE 64 + +/** + * struct vgetrandom_state - State used by vDSO getrandom(). + * + * @batch: One and a half ChaCha20 blocks of buffered RNG output. + * + * @key: Key to be used for generating next batch. + * + * @batch_key: Union of the prior two members, which is exactly two full + * ChaCha20 blocks in size, so that @batch and @key can be filled + * together. + * + * @generation: Snapshot of @rng_info->generation in the vDSO data page at + * the time @key was generated. + * + * @pos: Offset into @batch of the next available random byte. + * + * @in_use: Reentrancy guard for reusing a state within the same thread + * due to signal handlers. + */ +struct vgetrandom_state { + union { + struct { + u8 batch[CHACHA_BLOCK_SIZE * 3 / 2]; + u32 key[CHACHA_KEY_SIZE / sizeof(u32)]; + }; + u8 batch_key[CHACHA_BLOCK_SIZE * 2]; + }; + u64 generation; + u8 pos; + bool in_use; +}; + +#endif /* _VDSO_GETRANDOM_H */ |
