1 files changed, 136 insertions, 0 deletions
diff --git a/drivers/scsi/arm/arm_scsi.h b/drivers/scsi/arm/arm_scsi.h
new file mode 100644
index 000000000000..ea9fcd92c6de
--- /dev/null
+++ b/drivers/scsi/arm/arm_scsi.h
@@ -0,0 +1,136 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ *  Copyright (C) 2002 Russell King
+ *
+ *  Commonly used functions by the ARM SCSI-II drivers.
+ */
+
+#include <linux/scatterlist.h>
+
+#define BELT_AND_BRACES
+
+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);
+
+#ifdef BELT_AND_BRACES
+		{	/*
+			 * Calculate correct buffer length.  Some commands
+			 * come in with the wrong scsi_bufflen.
+			 */
+			struct scatterlist *sg;
+			unsigned i, sg_count = scsi_sg_count(SCpnt);
+
+			scsi_for_each_sg(SCpnt, sg, sg_count, i)
+				len += sg->length;
+
+			if (scsi_bufflen(SCpnt) != len) {
+				printk(KERN_WARNING
+				       "scsi%d.%c: bad request buffer "
+				       "length %d, should be %ld\n",
+					SCpnt->device->host->host_no,
+					'0' + SCpnt->device->id,
+					scsi_bufflen(SCpnt), len);
+				/*
+				 * FIXME: Totaly naive fixup. We should abort
+				 * with error
+				 */
+				scsi_pointer->phase =
+					min_t(unsigned long, len,
+					      scsi_bufflen(SCpnt));
+			}
+		}
+#endif
+	} else {
+		scsi_pointer->ptr = NULL;
+		scsi_pointer->this_residual = 0;
+		scsi_pointer->phase = 0;
+	}
+}