From 8a78362c4eefc1deddbefe2c7f38aabbc2429d6b Mon Sep 17 00:00:00 2001 From: "Martin K. Petersen" Date: Fri, 26 Feb 2010 00:20:39 -0500 Subject: block: Consolidate phys_segment and hw_segment limits Except for SCSI no device drivers distinguish between physical and hardware segment limits. Consolidate the two into a single segment limit. Signed-off-by: Martin K. Petersen Signed-off-by: Jens Axboe --- block/blk-core.c | 3 +-- block/blk-merge.c | 8 ++----- block/blk-settings.c | 60 ++++++++++++---------------------------------------- 3 files changed, 16 insertions(+), 55 deletions(-) (limited to 'block') diff --git a/block/blk-core.c b/block/blk-core.c index 36c0deebc2d..9fe174dc74d 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1614,8 +1614,7 @@ int blk_rq_check_limits(struct request_queue *q, struct request *rq) * limitation. */ blk_recalc_rq_segments(rq); - if (rq->nr_phys_segments > queue_max_phys_segments(q) || - rq->nr_phys_segments > queue_max_hw_segments(q)) { + if (rq->nr_phys_segments > queue_max_segments(q)) { printk(KERN_ERR "%s: over max segments limit.\n", __func__); return -EIO; } diff --git a/block/blk-merge.c b/block/blk-merge.c index 99cb5cf1f44..5e7dc997345 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -206,8 +206,7 @@ static inline int ll_new_hw_segment(struct request_queue *q, { int nr_phys_segs = bio_phys_segments(q, bio); - if (req->nr_phys_segments + nr_phys_segs > queue_max_hw_segments(q) || - req->nr_phys_segments + nr_phys_segs > queue_max_phys_segments(q)) { + if (req->nr_phys_segments + nr_phys_segs > queue_max_segments(q)) { req->cmd_flags |= REQ_NOMERGE; if (req == q->last_merge) q->last_merge = NULL; @@ -300,10 +299,7 @@ static int ll_merge_requests_fn(struct request_queue *q, struct request *req, total_phys_segments--; } - if (total_phys_segments > queue_max_phys_segments(q)) - return 0; - - if (total_phys_segments > queue_max_hw_segments(q)) + if (total_phys_segments > queue_max_segments(q)) return 0; /* Merge is OK... */ diff --git a/block/blk-settings.c b/block/blk-settings.c index 61afae9dbc6..31e7a9375c1 100644 --- a/block/blk-settings.c +++ b/block/blk-settings.c @@ -91,8 +91,7 @@ EXPORT_SYMBOL_GPL(blk_queue_lld_busy); */ void blk_set_default_limits(struct queue_limits *lim) { - lim->max_phys_segments = MAX_PHYS_SEGMENTS; - lim->max_hw_segments = MAX_HW_SEGMENTS; + lim->max_segments = BLK_MAX_SEGMENTS; lim->seg_boundary_mask = BLK_SEG_BOUNDARY_MASK; lim->max_segment_size = BLK_MAX_SEGMENT_SIZE; lim->max_sectors = BLK_DEF_MAX_SECTORS; @@ -252,17 +251,15 @@ void blk_queue_max_discard_sectors(struct request_queue *q, EXPORT_SYMBOL(blk_queue_max_discard_sectors); /** - * blk_queue_max_phys_segments - set max phys segments for a request for this queue + * blk_queue_max_segments - set max hw segments for a request for this queue * @q: the request queue for the device * @max_segments: max number of segments * * Description: * Enables a low level driver to set an upper limit on the number of - * physical data segments in a request. This would be the largest sized - * scatter list the driver could handle. + * hw data segments in a request. **/ -void blk_queue_max_phys_segments(struct request_queue *q, - unsigned short max_segments) +void blk_queue_max_segments(struct request_queue *q, unsigned short max_segments) { if (!max_segments) { max_segments = 1; @@ -270,33 +267,9 @@ void blk_queue_max_phys_segments(struct request_queue *q, __func__, max_segments); } - q->limits.max_phys_segments = max_segments; + q->limits.max_segments = max_segments; } -EXPORT_SYMBOL(blk_queue_max_phys_segments); - -/** - * blk_queue_max_hw_segments - set max hw segments for a request for this queue - * @q: the request queue for the device - * @max_segments: max number of segments - * - * Description: - * Enables a low level driver to set an upper limit on the number of - * hw data segments in a request. This would be the largest number of - * address/length pairs the host adapter can actually give at once - * to the device. - **/ -void blk_queue_max_hw_segments(struct request_queue *q, - unsigned short max_segments) -{ - if (!max_segments) { - max_segments = 1; - printk(KERN_INFO "%s: set to minimum %d\n", - __func__, max_segments); - } - - q->limits.max_hw_segments = max_segments; -} -EXPORT_SYMBOL(blk_queue_max_hw_segments); +EXPORT_SYMBOL(blk_queue_max_segments); /** * blk_queue_max_segment_size - set max segment size for blk_rq_map_sg @@ -531,11 +504,7 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, t->seg_boundary_mask = min_not_zero(t->seg_boundary_mask, b->seg_boundary_mask); - t->max_phys_segments = min_not_zero(t->max_phys_segments, - b->max_phys_segments); - - t->max_hw_segments = min_not_zero(t->max_hw_segments, - b->max_hw_segments); + t->max_segments = min_not_zero(t->max_segments, b->max_segments); t->max_segment_size = min_not_zero(t->max_segment_size, b->max_segment_size); @@ -739,22 +708,19 @@ EXPORT_SYMBOL(blk_queue_update_dma_pad); * does is adjust the queue so that the buf is always appended * silently to the scatterlist. * - * Note: This routine adjusts max_hw_segments to make room for - * appending the drain buffer. If you call - * blk_queue_max_hw_segments() or blk_queue_max_phys_segments() after - * calling this routine, you must set the limit to one fewer than your - * device can support otherwise there won't be room for the drain - * buffer. + * Note: This routine adjusts max_hw_segments to make room for appending + * the drain buffer. If you call blk_queue_max_segments() after calling + * this routine, you must set the limit to one fewer than your device + * can support otherwise there won't be room for the drain buffer. */ int blk_queue_dma_drain(struct request_queue *q, dma_drain_needed_fn *dma_drain_needed, void *buf, unsigned int size) { - if (queue_max_hw_segments(q) < 2 || queue_max_phys_segments(q) < 2) + if (queue_max_segments(q) < 2) return -EINVAL; /* make room for appending the drain */ - blk_queue_max_hw_segments(q, queue_max_hw_segments(q) - 1); - blk_queue_max_phys_segments(q, queue_max_phys_segments(q) - 1); + blk_queue_max_segments(q, queue_max_segments(q) - 1); q->dma_drain_needed = dma_drain_needed; q->dma_drain_buffer = buf; q->dma_drain_size = size; -- cgit v1.2.3