blk-mq: add support for carrying internal tag information in blk_qc_t

No functional change in this patch, just in preparation for having
two types of tags available to the block layer for a single request.

Signed-off-by: Jens Axboe <axboe@fb.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
This commit is contained in:
Jens Axboe
2017-01-12 10:04:45 -07:00
parent cc71a6f438
commit fd2d332677
2 changed files with 25 additions and 8 deletions

View File

@@ -232,22 +232,29 @@ static inline bool op_is_sync(unsigned int op)
}
typedef unsigned int blk_qc_t;
#define BLK_QC_T_NONE -1U
#define BLK_QC_T_SHIFT 16
#define BLK_QC_T_NONE -1U
#define BLK_QC_T_SHIFT 16
#define BLK_QC_T_INTERNAL (1U << 31)
static inline bool blk_qc_t_valid(blk_qc_t cookie)
{
return cookie != BLK_QC_T_NONE;
}
static inline blk_qc_t blk_tag_to_qc_t(unsigned int tag, unsigned int queue_num)
static inline blk_qc_t blk_tag_to_qc_t(unsigned int tag, unsigned int queue_num,
bool internal)
{
return tag | (queue_num << BLK_QC_T_SHIFT);
blk_qc_t ret = tag | (queue_num << BLK_QC_T_SHIFT);
if (internal)
ret |= BLK_QC_T_INTERNAL;
return ret;
}
static inline unsigned int blk_qc_t_to_queue_num(blk_qc_t cookie)
{
return cookie >> BLK_QC_T_SHIFT;
return (cookie & ~BLK_QC_T_INTERNAL) >> BLK_QC_T_SHIFT;
}
static inline unsigned int blk_qc_t_to_tag(blk_qc_t cookie)
@@ -255,6 +262,11 @@ static inline unsigned int blk_qc_t_to_tag(blk_qc_t cookie)
return cookie & ((1u << BLK_QC_T_SHIFT) - 1);
}
static inline bool blk_qc_t_is_internal(blk_qc_t cookie)
{
return (cookie & BLK_QC_T_INTERNAL) != 0;
}
struct blk_issue_stat {
u64 time;
};