Commit 86b37281 authored by Martin K. Petersen's avatar Martin K. Petersen Committed by Jens Axboe

block: Expose discard granularity

While SSDs track block usage on a per-sector basis, RAID arrays often
have allocation blocks that are bigger.  Allow the discard granularity
and alignment to be set and teach the topology stacking logic how to
handle them.
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
parent cf7c25cf
...@@ -96,7 +96,10 @@ void blk_set_default_limits(struct queue_limits *lim) ...@@ -96,7 +96,10 @@ void blk_set_default_limits(struct queue_limits *lim)
lim->max_segment_size = MAX_SEGMENT_SIZE; lim->max_segment_size = MAX_SEGMENT_SIZE;
lim->max_sectors = BLK_DEF_MAX_SECTORS; lim->max_sectors = BLK_DEF_MAX_SECTORS;
lim->max_hw_sectors = INT_MAX; lim->max_hw_sectors = INT_MAX;
lim->max_discard_sectors = SAFE_MAX_SECTORS; lim->max_discard_sectors = 0;
lim->discard_granularity = 0;
lim->discard_alignment = 0;
lim->discard_misaligned = 0;
lim->logical_block_size = lim->physical_block_size = lim->io_min = 512; lim->logical_block_size = lim->physical_block_size = lim->io_min = 512;
lim->bounce_pfn = (unsigned long)(BLK_BOUNCE_ANY >> PAGE_SHIFT); lim->bounce_pfn = (unsigned long)(BLK_BOUNCE_ANY >> PAGE_SHIFT);
lim->alignment_offset = 0; lim->alignment_offset = 0;
...@@ -488,6 +491,16 @@ void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b) ...@@ -488,6 +491,16 @@ void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b)
} }
EXPORT_SYMBOL(blk_queue_stack_limits); EXPORT_SYMBOL(blk_queue_stack_limits);
static unsigned int lcm(unsigned int a, unsigned int b)
{
if (a && b)
return (a * b) / gcd(a, b);
else if (b)
return b;
return a;
}
/** /**
* blk_stack_limits - adjust queue_limits for stacked devices * blk_stack_limits - adjust queue_limits for stacked devices
* @t: the stacking driver limits (top) * @t: the stacking driver limits (top)
...@@ -502,6 +515,10 @@ EXPORT_SYMBOL(blk_queue_stack_limits); ...@@ -502,6 +515,10 @@ EXPORT_SYMBOL(blk_queue_stack_limits);
int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
sector_t offset) sector_t offset)
{ {
int ret;
ret = 0;
t->max_sectors = min_not_zero(t->max_sectors, b->max_sectors); t->max_sectors = min_not_zero(t->max_sectors, b->max_sectors);
t->max_hw_sectors = min_not_zero(t->max_hw_sectors, b->max_hw_sectors); t->max_hw_sectors = min_not_zero(t->max_hw_sectors, b->max_hw_sectors);
t->bounce_pfn = min_not_zero(t->bounce_pfn, b->bounce_pfn); t->bounce_pfn = min_not_zero(t->bounce_pfn, b->bounce_pfn);
...@@ -531,7 +548,13 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, ...@@ -531,7 +548,13 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
if (offset && if (offset &&
(offset & (b->physical_block_size - 1)) != b->alignment_offset) { (offset & (b->physical_block_size - 1)) != b->alignment_offset) {
t->misaligned = 1; t->misaligned = 1;
return -1; ret = -1;
}
if (offset &&
(offset & (b->discard_granularity - 1)) != b->discard_alignment) {
t->discard_misaligned = 1;
ret = -1;
} }
/* If top has no alignment offset, inherit from bottom */ /* If top has no alignment offset, inherit from bottom */
...@@ -539,23 +562,26 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, ...@@ -539,23 +562,26 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
t->alignment_offset = t->alignment_offset =
b->alignment_offset & (b->physical_block_size - 1); b->alignment_offset & (b->physical_block_size - 1);
if (!t->discard_alignment)
t->discard_alignment =
b->discard_alignment & (b->discard_granularity - 1);
/* Top device aligned on logical block boundary? */ /* Top device aligned on logical block boundary? */
if (t->alignment_offset & (t->logical_block_size - 1)) { if (t->alignment_offset & (t->logical_block_size - 1)) {
t->misaligned = 1; t->misaligned = 1;
return -1; ret = -1;
} }
/* Find lcm() of optimal I/O size */ /* Find lcm() of optimal I/O size and granularity */
if (t->io_opt && b->io_opt) t->io_opt = lcm(t->io_opt, b->io_opt);
t->io_opt = (t->io_opt * b->io_opt) / gcd(t->io_opt, b->io_opt); t->discard_granularity = lcm(t->discard_granularity,
else if (b->io_opt) b->discard_granularity);
t->io_opt = b->io_opt;
/* Verify that optimal I/O size is a multiple of io_min */ /* Verify that optimal I/O size is a multiple of io_min */
if (t->io_min && t->io_opt % t->io_min) if (t->io_min && t->io_opt % t->io_min)
return -1; ret = -1;
return 0; return ret;
} }
EXPORT_SYMBOL(blk_stack_limits); EXPORT_SYMBOL(blk_stack_limits);
......
...@@ -126,6 +126,16 @@ static ssize_t queue_io_opt_show(struct request_queue *q, char *page) ...@@ -126,6 +126,16 @@ static ssize_t queue_io_opt_show(struct request_queue *q, char *page)
return queue_var_show(queue_io_opt(q), page); return queue_var_show(queue_io_opt(q), page);
} }
static ssize_t queue_discard_granularity_show(struct request_queue *q, char *page)
{
return queue_var_show(q->limits.discard_granularity, page);
}
static ssize_t queue_discard_max_show(struct request_queue *q, char *page)
{
return queue_var_show(q->limits.max_discard_sectors << 9, page);
}
static ssize_t static ssize_t
queue_max_sectors_store(struct request_queue *q, const char *page, size_t count) queue_max_sectors_store(struct request_queue *q, const char *page, size_t count)
{ {
...@@ -293,6 +303,16 @@ static struct queue_sysfs_entry queue_io_opt_entry = { ...@@ -293,6 +303,16 @@ static struct queue_sysfs_entry queue_io_opt_entry = {
.show = queue_io_opt_show, .show = queue_io_opt_show,
}; };
static struct queue_sysfs_entry queue_discard_granularity_entry = {
.attr = {.name = "discard_granularity", .mode = S_IRUGO },
.show = queue_discard_granularity_show,
};
static struct queue_sysfs_entry queue_discard_max_entry = {
.attr = {.name = "discard_max_bytes", .mode = S_IRUGO },
.show = queue_discard_max_show,
};
static struct queue_sysfs_entry queue_nonrot_entry = { static struct queue_sysfs_entry queue_nonrot_entry = {
.attr = {.name = "rotational", .mode = S_IRUGO | S_IWUSR }, .attr = {.name = "rotational", .mode = S_IRUGO | S_IWUSR },
.show = queue_nonrot_show, .show = queue_nonrot_show,
...@@ -328,6 +348,8 @@ static struct attribute *default_attrs[] = { ...@@ -328,6 +348,8 @@ static struct attribute *default_attrs[] = {
&queue_physical_block_size_entry.attr, &queue_physical_block_size_entry.attr,
&queue_io_min_entry.attr, &queue_io_min_entry.attr,
&queue_io_opt_entry.attr, &queue_io_opt_entry.attr,
&queue_discard_granularity_entry.attr,
&queue_discard_max_entry.attr,
&queue_nonrot_entry.attr, &queue_nonrot_entry.attr,
&queue_nomerges_entry.attr, &queue_nomerges_entry.attr,
&queue_rq_affinity_entry.attr, &queue_rq_affinity_entry.attr,
......
...@@ -861,12 +861,23 @@ static ssize_t disk_alignment_offset_show(struct device *dev, ...@@ -861,12 +861,23 @@ static ssize_t disk_alignment_offset_show(struct device *dev,
return sprintf(buf, "%d\n", queue_alignment_offset(disk->queue)); return sprintf(buf, "%d\n", queue_alignment_offset(disk->queue));
} }
static ssize_t disk_discard_alignment_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct gendisk *disk = dev_to_disk(dev);
return sprintf(buf, "%u\n", queue_discard_alignment(disk->queue));
}
static DEVICE_ATTR(range, S_IRUGO, disk_range_show, NULL); static DEVICE_ATTR(range, S_IRUGO, disk_range_show, NULL);
static DEVICE_ATTR(ext_range, S_IRUGO, disk_ext_range_show, NULL); static DEVICE_ATTR(ext_range, S_IRUGO, disk_ext_range_show, NULL);
static DEVICE_ATTR(removable, S_IRUGO, disk_removable_show, NULL); static DEVICE_ATTR(removable, S_IRUGO, disk_removable_show, NULL);
static DEVICE_ATTR(ro, S_IRUGO, disk_ro_show, NULL); static DEVICE_ATTR(ro, S_IRUGO, disk_ro_show, NULL);
static DEVICE_ATTR(size, S_IRUGO, part_size_show, NULL); static DEVICE_ATTR(size, S_IRUGO, part_size_show, NULL);
static DEVICE_ATTR(alignment_offset, S_IRUGO, disk_alignment_offset_show, NULL); static DEVICE_ATTR(alignment_offset, S_IRUGO, disk_alignment_offset_show, NULL);
static DEVICE_ATTR(discard_alignment, S_IRUGO, disk_discard_alignment_show,
NULL);
static DEVICE_ATTR(capability, S_IRUGO, disk_capability_show, NULL); static DEVICE_ATTR(capability, S_IRUGO, disk_capability_show, NULL);
static DEVICE_ATTR(stat, S_IRUGO, part_stat_show, NULL); static DEVICE_ATTR(stat, S_IRUGO, part_stat_show, NULL);
static DEVICE_ATTR(inflight, S_IRUGO, part_inflight_show, NULL); static DEVICE_ATTR(inflight, S_IRUGO, part_inflight_show, NULL);
...@@ -887,6 +898,7 @@ static struct attribute *disk_attrs[] = { ...@@ -887,6 +898,7 @@ static struct attribute *disk_attrs[] = {
&dev_attr_ro.attr, &dev_attr_ro.attr,
&dev_attr_size.attr, &dev_attr_size.attr,
&dev_attr_alignment_offset.attr, &dev_attr_alignment_offset.attr,
&dev_attr_discard_alignment.attr,
&dev_attr_capability.attr, &dev_attr_capability.attr,
&dev_attr_stat.attr, &dev_attr_stat.attr,
&dev_attr_inflight.attr, &dev_attr_inflight.attr,
......
...@@ -226,6 +226,13 @@ ssize_t part_alignment_offset_show(struct device *dev, ...@@ -226,6 +226,13 @@ ssize_t part_alignment_offset_show(struct device *dev,
return sprintf(buf, "%llu\n", (unsigned long long)p->alignment_offset); return sprintf(buf, "%llu\n", (unsigned long long)p->alignment_offset);
} }
ssize_t part_discard_alignment_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct hd_struct *p = dev_to_part(dev);
return sprintf(buf, "%u\n", p->discard_alignment);
}
ssize_t part_stat_show(struct device *dev, ssize_t part_stat_show(struct device *dev,
struct device_attribute *attr, char *buf) struct device_attribute *attr, char *buf)
{ {
...@@ -288,6 +295,8 @@ static DEVICE_ATTR(partition, S_IRUGO, part_partition_show, NULL); ...@@ -288,6 +295,8 @@ static DEVICE_ATTR(partition, S_IRUGO, part_partition_show, NULL);
static DEVICE_ATTR(start, S_IRUGO, part_start_show, NULL); static DEVICE_ATTR(start, S_IRUGO, part_start_show, NULL);
static DEVICE_ATTR(size, S_IRUGO, part_size_show, NULL); static DEVICE_ATTR(size, S_IRUGO, part_size_show, NULL);
static DEVICE_ATTR(alignment_offset, S_IRUGO, part_alignment_offset_show, NULL); static DEVICE_ATTR(alignment_offset, S_IRUGO, part_alignment_offset_show, NULL);
static DEVICE_ATTR(discard_alignment, S_IRUGO, part_discard_alignment_show,
NULL);
static DEVICE_ATTR(stat, S_IRUGO, part_stat_show, NULL); static DEVICE_ATTR(stat, S_IRUGO, part_stat_show, NULL);
static DEVICE_ATTR(inflight, S_IRUGO, part_inflight_show, NULL); static DEVICE_ATTR(inflight, S_IRUGO, part_inflight_show, NULL);
#ifdef CONFIG_FAIL_MAKE_REQUEST #ifdef CONFIG_FAIL_MAKE_REQUEST
...@@ -300,6 +309,7 @@ static struct attribute *part_attrs[] = { ...@@ -300,6 +309,7 @@ static struct attribute *part_attrs[] = {
&dev_attr_start.attr, &dev_attr_start.attr,
&dev_attr_size.attr, &dev_attr_size.attr,
&dev_attr_alignment_offset.attr, &dev_attr_alignment_offset.attr,
&dev_attr_discard_alignment.attr,
&dev_attr_stat.attr, &dev_attr_stat.attr,
&dev_attr_inflight.attr, &dev_attr_inflight.attr,
#ifdef CONFIG_FAIL_MAKE_REQUEST #ifdef CONFIG_FAIL_MAKE_REQUEST
...@@ -403,6 +413,8 @@ struct hd_struct *add_partition(struct gendisk *disk, int partno, ...@@ -403,6 +413,8 @@ struct hd_struct *add_partition(struct gendisk *disk, int partno,
p->start_sect = start; p->start_sect = start;
p->alignment_offset = queue_sector_alignment_offset(disk->queue, start); p->alignment_offset = queue_sector_alignment_offset(disk->queue, start);
p->discard_alignment = queue_sector_discard_alignment(disk->queue,
start);
p->nr_sects = len; p->nr_sects = len;
p->partno = partno; p->partno = partno;
p->policy = get_disk_ro(disk); p->policy = get_disk_ro(disk);
......
...@@ -312,12 +312,15 @@ struct queue_limits { ...@@ -312,12 +312,15 @@ struct queue_limits {
unsigned int io_min; unsigned int io_min;
unsigned int io_opt; unsigned int io_opt;
unsigned int max_discard_sectors; unsigned int max_discard_sectors;
unsigned int discard_granularity;
unsigned int discard_alignment;
unsigned short logical_block_size; unsigned short logical_block_size;
unsigned short max_hw_segments; unsigned short max_hw_segments;
unsigned short max_phys_segments; unsigned short max_phys_segments;
unsigned char misaligned; unsigned char misaligned;
unsigned char discard_misaligned;
unsigned char no_cluster; unsigned char no_cluster;
}; };
...@@ -1121,6 +1124,21 @@ static inline int bdev_alignment_offset(struct block_device *bdev) ...@@ -1121,6 +1124,21 @@ static inline int bdev_alignment_offset(struct block_device *bdev)
return q->limits.alignment_offset; return q->limits.alignment_offset;
} }
static inline int queue_discard_alignment(struct request_queue *q)
{
if (q->limits.discard_misaligned)
return -1;
return q->limits.discard_alignment;
}
static inline int queue_sector_discard_alignment(struct request_queue *q,
sector_t sector)
{
return ((sector << 9) - q->limits.discard_alignment)
& (q->limits.discard_granularity - 1);
}
static inline int queue_dma_alignment(struct request_queue *q) static inline int queue_dma_alignment(struct request_queue *q)
{ {
return q ? q->dma_alignment : 511; return q ? q->dma_alignment : 511;
......
...@@ -91,6 +91,7 @@ struct hd_struct { ...@@ -91,6 +91,7 @@ struct hd_struct {
sector_t start_sect; sector_t start_sect;
sector_t nr_sects; sector_t nr_sects;
sector_t alignment_offset; sector_t alignment_offset;
unsigned int discard_alignment;
struct device __dev; struct device __dev;
struct kobject *holder_dir; struct kobject *holder_dir;
int policy, partno; int policy, partno;
......
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