diff options
Diffstat (limited to 'drivers/scsi/arm/arm_scsi.h')
-rw-r--r-- | drivers/scsi/arm/arm_scsi.h | 136 |
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 000000000..ea9fcd92c --- /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; + } +} |