arch/hexagon/mm/copy_from_user.S

Source file repositories/reference/linux-study-clean/arch/hexagon/mm/copy_from_user.S

File Facts

System
Linux kernel
Corpus path
arch/hexagon/mm/copy_from_user.S
Extension
.S
Size
1687 bytes
Lines
102
Domain
Architecture Layer
Bucket
arch/hexagon
Inferred role
Architecture Layer: arch/hexagon
Status
atlas-only

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

#define src_sav r13
#define dst_sav r12
#define src_dst_sav r13:12
#define d_dbuf r15:14
#define w_dbuf r15

#define dst r0
#define src r1
#define bytes r2
#define loopcount r5

#define FUNCNAME raw_copy_from_user
#include "copy_user_template.S"

	/* LOAD FAULTS from COPY_FROM_USER */

	/* Alignment loop.  r2 has been updated. Return it. */
	.falign
1009:
2009:
4009:
	{
		r0 = r2
		jumpr r31
	}
	/* Normal copy loops. Do epilog. Use src-src_sav to compute distance */
	/* X - (A - B) == X + B - A */
	.falign
8089:
	{
		memd(dst) = d_dbuf
		r2 += sub(src_sav,src)
	}
	{
		r0 = r2
		jumpr r31
	}
	.falign
4089:
	{
		memw(dst) = w_dbuf
		r2 += sub(src_sav,src)
	}
	{
		r0 = r2
		jumpr r31
	}
	.falign
2089:
	{
		memh(dst) = w_dbuf
		r2 += sub(src_sav,src)
	}
	{
		r0 = r2
		jumpr r31
	}
	.falign
1089:
	{
		memb(dst) = w_dbuf
		r2 += sub(src_sav,src)
	}
	{
		r0 = r2
		jumpr r31
	}

	/* COPY FROM USER: only loads can fail */

Annotation

Implementation Notes