lib/crc/mips/crc32.h

Source file repositories/reference/linux-study-clean/lib/crc/mips/crc32.h

File Facts

System
Linux kernel
Corpus path
lib/crc/mips/crc32.h
Extension
.h
Size
4068 bytes
Lines
163
Domain
Kernel Services
Bucket
lib
Inferred role
Kernel Services: implementation source
Status
source implementation candidate

Why This File Exists

Shared kernel service surface used by multiple subsystems, including helpers, cryptography, virtualization support, and async I/O infrastructure.

Dependency Surface

Detected Declarations

Annotated Snippet

if (len & sizeof(u32)) {
			u32 value = get_unaligned_le32(p);

			CRC32(crc, value, w);
			p += sizeof(u32);
		}
	} else {
		for (; len >= sizeof(u32); len -= sizeof(u32)) {
			u32 value = get_unaligned_le32(p);

			CRC32(crc, value, w);
			p += sizeof(u32);
		}
	}

	if (len & sizeof(u16)) {
		u16 value = get_unaligned_le16(p);

		CRC32(crc, value, h);
		p += sizeof(u16);
	}

	if (len & sizeof(u8)) {
		u8 value = *p++;

		CRC32(crc, value, b);
	}

	return crc;
}

static inline u32 crc32c_arch(u32 crc, const u8 *p, size_t len)
{
	if (!static_branch_likely(&have_crc32))
		return crc32c_base(crc, p, len);

	if (IS_ENABLED(CONFIG_64BIT)) {
		for (; len >= sizeof(u64); p += sizeof(u64), len -= sizeof(u64)) {
			u64 value = get_unaligned_le64(p);

			CRC32C(crc, value, d);
		}

		if (len & sizeof(u32)) {
			u32 value = get_unaligned_le32(p);

			CRC32C(crc, value, w);
			p += sizeof(u32);
		}
	} else {
		for (; len >= sizeof(u32); len -= sizeof(u32)) {
			u32 value = get_unaligned_le32(p);

			CRC32C(crc, value, w);
			p += sizeof(u32);
		}
	}

	if (len & sizeof(u16)) {
		u16 value = get_unaligned_le16(p);

		CRC32C(crc, value, h);
		p += sizeof(u16);
	}

	if (len & sizeof(u8)) {
		u8 value = *p++;

		CRC32C(crc, value, b);
	}
	return crc;
}

#define crc32_be_arch crc32_be_base /* not implemented on this arch */

#define crc32_mod_init_arch crc32_mod_init_arch
static void crc32_mod_init_arch(void)
{
	if (cpu_have_feature(cpu_feature(MIPS_CRC32)))
		static_branch_enable(&have_crc32);
}

static inline u32 crc32_optimizations_arch(void)
{
	if (static_key_enabled(&have_crc32))
		return CRC32_LE_OPTIMIZATION | CRC32C_OPTIMIZATION;
	return 0;
}

Annotation

Implementation Notes