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Diffstat (limited to 'block/blk-settings.c')
-rw-r--r--block/blk-settings.c88
1 files changed, 55 insertions, 33 deletions
diff --git a/block/blk-settings.c b/block/blk-settings.c
index 7541ea4bf9f..476d8706507 100644
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -7,6 +7,7 @@
#include <linux/bio.h>
#include <linux/blkdev.h>
#include <linux/bootmem.h> /* for max_pfn/max_low_pfn */
+#include <linux/gcd.h>
#include "blk.h"
@@ -97,7 +98,7 @@ EXPORT_SYMBOL_GPL(blk_queue_lld_busy);
/**
* blk_set_default_limits - reset limits to default values
- * @limits: the queue_limits structure to reset
+ * @lim: the queue_limits structure to reset
*
* Description:
* Returns a queue_limit struct to its default state. Can be used by
@@ -112,7 +113,7 @@ void blk_set_default_limits(struct queue_limits *lim)
lim->max_segment_size = MAX_SEGMENT_SIZE;
lim->max_sectors = lim->max_hw_sectors = SAFE_MAX_SECTORS;
lim->logical_block_size = lim->physical_block_size = lim->io_min = 512;
- lim->bounce_pfn = BLK_BOUNCE_ANY;
+ lim->bounce_pfn = (unsigned long)(BLK_BOUNCE_ANY >> PAGE_SHIFT);
lim->alignment_offset = 0;
lim->io_opt = 0;
lim->misaligned = 0;
@@ -165,6 +166,13 @@ void blk_queue_make_request(struct request_queue *q, make_request_fn *mfn)
blk_set_default_limits(&q->limits);
/*
+ * If the caller didn't supply a lock, fall back to our embedded
+ * per-queue locks
+ */
+ if (!q->queue_lock)
+ q->queue_lock = &q->__queue_lock;
+
+ /*
* by default assume old behaviour and bounce for any highmem page
*/
blk_queue_bounce_limit(q, BLK_BOUNCE_HIGH);
@@ -377,8 +385,8 @@ void blk_queue_alignment_offset(struct request_queue *q, unsigned int offset)
EXPORT_SYMBOL(blk_queue_alignment_offset);
/**
- * blk_queue_io_min - set minimum request size for the queue
- * @q: the request queue for the device
+ * blk_limits_io_min - set minimum request size for a device
+ * @limits: the queue limits
* @min: smallest I/O size in bytes
*
* Description:
@@ -387,15 +395,35 @@ EXPORT_SYMBOL(blk_queue_alignment_offset);
* smallest I/O the device can perform without incurring a performance
* penalty.
*/
-void blk_queue_io_min(struct request_queue *q, unsigned int min)
+void blk_limits_io_min(struct queue_limits *limits, unsigned int min)
{
- q->limits.io_min = min;
+ limits->io_min = min;
- if (q->limits.io_min < q->limits.logical_block_size)
- q->limits.io_min = q->limits.logical_block_size;
+ if (limits->io_min < limits->logical_block_size)
+ limits->io_min = limits->logical_block_size;
- if (q->limits.io_min < q->limits.physical_block_size)
- q->limits.io_min = q->limits.physical_block_size;
+ if (limits->io_min < limits->physical_block_size)
+ limits->io_min = limits->physical_block_size;
+}
+EXPORT_SYMBOL(blk_limits_io_min);
+
+/**
+ * blk_queue_io_min - set minimum request size for the queue
+ * @q: the request queue for the device
+ * @min: smallest I/O size in bytes
+ *
+ * Description:
+ * Storage devices may report a granularity or preferred minimum I/O
+ * size which is the smallest request the device can perform without
+ * incurring a performance penalty. For disk drives this is often the
+ * physical block size. For RAID arrays it is often the stripe chunk
+ * size. A properly aligned multiple of minimum_io_size is the
+ * preferred request size for workloads where a high number of I/O
+ * operations is desired.
+ */
+void blk_queue_io_min(struct request_queue *q, unsigned int min)
+{
+ blk_limits_io_min(&q->limits, min);
}
EXPORT_SYMBOL(blk_queue_io_min);
@@ -405,8 +433,12 @@ EXPORT_SYMBOL(blk_queue_io_min);
* @opt: optimal request size in bytes
*
* Description:
- * Drivers can call this function to set the preferred I/O request
- * size for devices that report such a value.
+ * Storage devices may report an optimal I/O size, which is the
+ * device's preferred unit for sustained I/O. This is rarely reported
+ * for disk drives. For RAID arrays it is usually the stripe width or
+ * the internal track size. A properly aligned multiple of
+ * optimal_io_size is the preferred request size for workloads where
+ * sustained throughput is desired.
*/
void blk_queue_io_opt(struct request_queue *q, unsigned int opt)
{
@@ -426,27 +458,7 @@ EXPORT_SYMBOL(blk_queue_io_opt);
**/
void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b)
{
- /* zero is "infinity" */
- t->limits.max_sectors = min_not_zero(queue_max_sectors(t),
- queue_max_sectors(b));
-
- t->limits.max_hw_sectors = min_not_zero(queue_max_hw_sectors(t),
- queue_max_hw_sectors(b));
-
- t->limits.seg_boundary_mask = min_not_zero(queue_segment_boundary(t),
- queue_segment_boundary(b));
-
- t->limits.max_phys_segments = min_not_zero(queue_max_phys_segments(t),
- queue_max_phys_segments(b));
-
- t->limits.max_hw_segments = min_not_zero(queue_max_hw_segments(t),
- queue_max_hw_segments(b));
-
- t->limits.max_segment_size = min_not_zero(queue_max_segment_size(t),
- queue_max_segment_size(b));
-
- t->limits.logical_block_size = max(queue_logical_block_size(t),
- queue_logical_block_size(b));
+ blk_stack_limits(&t->limits, &b->limits, 0);
if (!t->queue_lock)
WARN_ON_ONCE(1);
@@ -516,6 +528,16 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
return -1;
}
+ /* Find lcm() of optimal I/O size */
+ if (t->io_opt && b->io_opt)
+ t->io_opt = (t->io_opt * b->io_opt) / gcd(t->io_opt, b->io_opt);
+ else if (b->io_opt)
+ t->io_opt = b->io_opt;
+
+ /* Verify that optimal I/O size is a multiple of io_min */
+ if (t->io_min && t->io_opt % t->io_min)
+ return -1;
+
return 0;
}
EXPORT_SYMBOL(blk_stack_limits);