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Diffstat (limited to 'drivers/scsi/arm/arm_scsi.h')
-rw-r--r--drivers/scsi/arm/arm_scsi.h123
1 files changed, 123 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..3eb5c6aa93c9
--- /dev/null
+++ b/drivers/scsi/arm/arm_scsi.h
@@ -0,0 +1,123 @@
+/* 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
+
+/*
+ * 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)
+{
+ memset(&SCpnt->SCp, 0, sizeof(struct scsi_pointer));
+
+ if (scsi_bufflen(SCpnt)) {
+ unsigned long len = 0;
+
+ SCpnt->SCp.buffer = scsi_sglist(SCpnt);
+ SCpnt->SCp.buffers_residual = scsi_sg_count(SCpnt) - 1;
+ SCpnt->SCp.ptr = sg_virt(SCpnt->SCp.buffer);
+ SCpnt->SCp.this_residual = SCpnt->SCp.buffer->length;
+ SCpnt->SCp.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
+ */
+ SCpnt->SCp.phase =
+ min_t(unsigned long, len,
+ scsi_bufflen(SCpnt));
+ }
+ }
+#endif
+ } else {
+ SCpnt->SCp.ptr = NULL;
+ SCpnt->SCp.this_residual = 0;
+ SCpnt->SCp.phase = 0;
+ }
+}