drivers/scsi/arm/arm_scsi.h

Source file repositories/reference/linux-study-clean/drivers/scsi/arm/arm_scsi.h

File Facts

System
Linux kernel
Corpus path
drivers/scsi/arm/arm_scsi.h
Extension
.h
Size
3157 bytes
Lines
137
Domain
Driver Families
Bucket
drivers/scsi
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

struct arm_cmd_priv {
	struct scsi_pointer scsi_pointer;
};

static inline struct scsi_pointer *arm_scsi_pointer(struct scsi_cmnd *cmd)
{
	struct arm_cmd_priv *acmd = scsi_cmd_priv(cmd);

	return &acmd->scsi_pointer;
}

/*
 * The scatter-gather list handling.  This contains all
 * the yucky stuff that needs to be fixed properly.
 */

/*
 * copy_SCp_to_sg() Assumes contiguous allocation at @sg of at-most @max
 * entries of uninitialized memory. SCp is from scsi-ml and has a valid
 * (possibly chained) sg-list
 */
static inline int copy_SCp_to_sg(struct scatterlist *sg, struct scsi_pointer *SCp, int max)
{
	int bufs = SCp->buffers_residual;

	/* FIXME: It should be easy for drivers to loop on copy_SCp_to_sg().
	 * and to remove this BUG_ON. Use min() in-its-place
	 */
	BUG_ON(bufs + 1 > max);

	sg_set_buf(sg, SCp->ptr, SCp->this_residual);

	if (bufs) {
		struct scatterlist *src_sg;
		unsigned i;

		for_each_sg(sg_next(SCp->buffer), src_sg, bufs, i)
			*(++sg) = *src_sg;
		sg_mark_end(sg);
	}

	return bufs + 1;
}

static inline int next_SCp(struct scsi_pointer *SCp)
{
	int ret = SCp->buffers_residual;
	if (ret) {
		SCp->buffer = sg_next(SCp->buffer);
		SCp->buffers_residual--;
		SCp->ptr = sg_virt(SCp->buffer);
		SCp->this_residual = SCp->buffer->length;
	} else {
		SCp->ptr = NULL;
		SCp->this_residual = 0;
	}
	return ret;
}

static inline unsigned char get_next_SCp_byte(struct scsi_pointer *SCp)
{
	char c = *SCp->ptr;

	SCp->ptr += 1;
	SCp->this_residual -= 1;

	return c;
}

static inline void put_next_SCp_byte(struct scsi_pointer *SCp, unsigned char c)
{
	*SCp->ptr = c;
	SCp->ptr += 1;
	SCp->this_residual -= 1;
}

static inline void init_SCp(struct scsi_cmnd *SCpnt)
{
	struct scsi_pointer *scsi_pointer = arm_scsi_pointer(SCpnt);

	memset(scsi_pointer, 0, sizeof(struct scsi_pointer));

	if (scsi_bufflen(SCpnt)) {
		unsigned long len = 0;

		scsi_pointer->buffer = scsi_sglist(SCpnt);
		scsi_pointer->buffers_residual = scsi_sg_count(SCpnt) - 1;
		scsi_pointer->ptr = sg_virt(scsi_pointer->buffer);
		scsi_pointer->this_residual = scsi_pointer->buffer->length;
		scsi_pointer->phase = scsi_bufflen(SCpnt);

Annotation

Implementation Notes