cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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t10-pi.h (2217B)

      1/* SPDX-License-Identifier: GPL-2.0 */
      2#ifndef _LINUX_T10_PI_H
      3#define _LINUX_T10_PI_H
      4
      5#include <linux/types.h>
      6#include <linux/blk-mq.h>
      7
      8/*
      9 * A T10 PI-capable target device can be formatted with different
     10 * protection schemes.	Currently 0 through 3 are defined:
     11 *
     12 * Type 0 is regular (unprotected) I/O
     13 *
     14 * Type 1 defines the contents of the guard and reference tags
     15 *
     16 * Type 2 defines the contents of the guard and reference tags and
     17 * uses 32-byte commands to seed the latter
     18 *
     19 * Type 3 defines the contents of the guard tag only
     20 */
     21enum t10_dif_type {
     22	T10_PI_TYPE0_PROTECTION = 0x0,
     23	T10_PI_TYPE1_PROTECTION = 0x1,
     24	T10_PI_TYPE2_PROTECTION = 0x2,
     25	T10_PI_TYPE3_PROTECTION = 0x3,
     26};
     27
     28/*
     29 * T10 Protection Information tuple.
     30 */
     31struct t10_pi_tuple {
     32	__be16 guard_tag;	/* Checksum */
     33	__be16 app_tag;		/* Opaque storage */
     34	__be32 ref_tag;		/* Target LBA or indirect LBA */
     35};
     36
     37#define T10_PI_APP_ESCAPE cpu_to_be16(0xffff)
     38#define T10_PI_REF_ESCAPE cpu_to_be32(0xffffffff)
     39
     40static inline u32 t10_pi_ref_tag(struct request *rq)
     41{
     42	unsigned int shift = ilog2(queue_logical_block_size(rq->q));
     43
     44#ifdef CONFIG_BLK_DEV_INTEGRITY
     45	if (rq->q->integrity.interval_exp)
     46		shift = rq->q->integrity.interval_exp;
     47#endif
     48	return blk_rq_pos(rq) >> (shift - SECTOR_SHIFT) & 0xffffffff;
     49}
     50
     51extern const struct blk_integrity_profile t10_pi_type1_crc;
     52extern const struct blk_integrity_profile t10_pi_type1_ip;
     53extern const struct blk_integrity_profile t10_pi_type3_crc;
     54extern const struct blk_integrity_profile t10_pi_type3_ip;
     55
     56struct crc64_pi_tuple {
     57	__be64 guard_tag;
     58	__be16 app_tag;
     59	__u8   ref_tag[6];
     60};
     61
     62/**
     63 * lower_48_bits() - return bits 0-47 of a number
     64 * @n: the number we're accessing
     65 */
     66static inline u64 lower_48_bits(u64 n)
     67{
     68	return n & ((1ull << 48) - 1);
     69}
     70
     71static inline u64 ext_pi_ref_tag(struct request *rq)
     72{
     73	unsigned int shift = ilog2(queue_logical_block_size(rq->q));
     74
     75#ifdef CONFIG_BLK_DEV_INTEGRITY
     76	if (rq->q->integrity.interval_exp)
     77		shift = rq->q->integrity.interval_exp;
     78#endif
     79	return lower_48_bits(blk_rq_pos(rq) >> (shift - SECTOR_SHIFT));
     80}
     81
     82extern const struct blk_integrity_profile ext_pi_type1_crc64;
     83extern const struct blk_integrity_profile ext_pi_type3_crc64;
     84
     85#endif