diff mbox series

[RFC,1/8] block: Introduce provisioning primitives

Message ID 20220915164826.1396245-2-sarthakkukreti@google.com
State Not Applicable
Headers show
Series Introduce provisioning primitives for thinly provisioned storage | expand

Commit Message

Sarthak Kukreti Sept. 15, 2022, 4:48 p.m. UTC
From: Sarthak Kukreti <sarthakkukreti@chromium.org>

Introduce block request REQ_OP_PROVISION. The intent of this request
is to request underlying storage to preallocate disk space for the given
block range. Block device that support this capability will export
a provision limit within their request queues.

Signed-off-by: Sarthak Kukreti <sarthakkukreti@chromium.org>
---
 block/blk-core.c          |  5 ++++
 block/blk-lib.c           | 55 +++++++++++++++++++++++++++++++++++++++
 block/blk-merge.c         | 17 ++++++++++++
 block/blk-settings.c      | 19 ++++++++++++++
 block/blk-sysfs.c         |  8 ++++++
 block/bounce.c            |  1 +
 include/linux/bio.h       |  6 +++--
 include/linux/blk_types.h |  5 +++-
 include/linux/blkdev.h    | 16 ++++++++++++
 9 files changed, 129 insertions(+), 3 deletions(-)

Comments

Mike Snitzer Sept. 23, 2022, 3:15 p.m. UTC | #1
On Thu, Sep 15 2022 at 12:48P -0400,
Sarthak Kukreti <sarthakkukreti@chromium.org> wrote:

> From: Sarthak Kukreti <sarthakkukreti@chromium.org>
> 
> Introduce block request REQ_OP_PROVISION. The intent of this request
> is to request underlying storage to preallocate disk space for the given
> block range. Block device that support this capability will export
> a provision limit within their request queues.
> 
> Signed-off-by: Sarthak Kukreti <sarthakkukreti@chromium.org>
> ---
>  block/blk-core.c          |  5 ++++
>  block/blk-lib.c           | 55 +++++++++++++++++++++++++++++++++++++++
>  block/blk-merge.c         | 17 ++++++++++++
>  block/blk-settings.c      | 19 ++++++++++++++
>  block/blk-sysfs.c         |  8 ++++++
>  block/bounce.c            |  1 +
>  include/linux/bio.h       |  6 +++--
>  include/linux/blk_types.h |  5 +++-
>  include/linux/blkdev.h    | 16 ++++++++++++
>  9 files changed, 129 insertions(+), 3 deletions(-)
> 
> diff --git a/block/blk-settings.c b/block/blk-settings.c
> index 8bb9eef5310e..be79ad68b330 100644
> --- a/block/blk-settings.c
> +++ b/block/blk-settings.c
> @@ -57,6 +57,7 @@ void blk_set_default_limits(struct queue_limits *lim)
>  	lim->misaligned = 0;
>  	lim->zoned = BLK_ZONED_NONE;
>  	lim->zone_write_granularity = 0;
> +	lim->max_provision_sectors = 0;
>  }
>  EXPORT_SYMBOL(blk_set_default_limits);
>  
> @@ -81,6 +82,7 @@ void blk_set_stacking_limits(struct queue_limits *lim)
>  	lim->max_dev_sectors = UINT_MAX;
>  	lim->max_write_zeroes_sectors = UINT_MAX;
>  	lim->max_zone_append_sectors = UINT_MAX;
> +	lim->max_provision_sectors = UINT_MAX;
>  }
>  EXPORT_SYMBOL(blk_set_stacking_limits);
>  

Please work through the blk_stack_limits() implementation too (simple
min_not_zero?).
Sarthak Kukreti Dec. 29, 2022, 8:17 a.m. UTC | #2
On Fri, Sep 23, 2022 at 8:15 AM Mike Snitzer <snitzer@redhat.com> wrote:
>
> On Thu, Sep 15 2022 at 12:48P -0400,
> Sarthak Kukreti <sarthakkukreti@chromium.org> wrote:
>
> > From: Sarthak Kukreti <sarthakkukreti@chromium.org>
> >
> > Introduce block request REQ_OP_PROVISION. The intent of this request
> > is to request underlying storage to preallocate disk space for the given
> > block range. Block device that support this capability will export
> > a provision limit within their request queues.
> >
> > Signed-off-by: Sarthak Kukreti <sarthakkukreti@chromium.org>
> > ---
> >  block/blk-core.c          |  5 ++++
> >  block/blk-lib.c           | 55 +++++++++++++++++++++++++++++++++++++++
> >  block/blk-merge.c         | 17 ++++++++++++
> >  block/blk-settings.c      | 19 ++++++++++++++
> >  block/blk-sysfs.c         |  8 ++++++
> >  block/bounce.c            |  1 +
> >  include/linux/bio.h       |  6 +++--
> >  include/linux/blk_types.h |  5 +++-
> >  include/linux/blkdev.h    | 16 ++++++++++++
> >  9 files changed, 129 insertions(+), 3 deletions(-)
> >
> > diff --git a/block/blk-settings.c b/block/blk-settings.c
> > index 8bb9eef5310e..be79ad68b330 100644
> > --- a/block/blk-settings.c
> > +++ b/block/blk-settings.c
> > @@ -57,6 +57,7 @@ void blk_set_default_limits(struct queue_limits *lim)
> >       lim->misaligned = 0;
> >       lim->zoned = BLK_ZONED_NONE;
> >       lim->zone_write_granularity = 0;
> > +     lim->max_provision_sectors = 0;
> >  }
> >  EXPORT_SYMBOL(blk_set_default_limits);
> >
> > @@ -81,6 +82,7 @@ void blk_set_stacking_limits(struct queue_limits *lim)
> >       lim->max_dev_sectors = UINT_MAX;
> >       lim->max_write_zeroes_sectors = UINT_MAX;
> >       lim->max_zone_append_sectors = UINT_MAX;
> > +     lim->max_provision_sectors = UINT_MAX;
> >  }
> >  EXPORT_SYMBOL(blk_set_stacking_limits);
> >
>
> Please work through the blk_stack_limits() implementation too (simple
> min_not_zero?).
>
(Sorry, I might have misunderstood what you meant) Doesn't the chunk
at L572 handle this:


@@ -572,6 +588,9 @@ int blk_stack_limits(struct queue_limits *t,
struct queue_limits *b,
        t->max_segment_size = min_not_zero(t->max_segment_size,
                                           b->max_segment_size);

+       t->max_provision_sectors = min_not_zero(t->max_provision_sectors,
+                                               b->max_provision_sectors);
+
        t->misaligned |= b->misaligned;
diff mbox series

Patch

diff --git a/block/blk-core.c b/block/blk-core.c
index a0d1104c5590..affefbaba1cd 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -125,6 +125,7 @@  static const char *const blk_op_name[] = {
 	REQ_OP_NAME(WRITE_ZEROES),
 	REQ_OP_NAME(DRV_IN),
 	REQ_OP_NAME(DRV_OUT),
+	REQ_OP_NAME(PROVISION)
 };
 #undef REQ_OP_NAME
 
@@ -776,6 +777,10 @@  void submit_bio_noacct(struct bio *bio)
 		if (!q->limits.max_write_zeroes_sectors)
 			goto not_supported;
 		break;
+	case REQ_OP_PROVISION:
+		if (!q->limits.max_provision_sectors)
+			goto not_supported;
+		break;
 	default:
 		break;
 	}
diff --git a/block/blk-lib.c b/block/blk-lib.c
index 67e6dbc1ae81..dc11ed29b523 100644
--- a/block/blk-lib.c
+++ b/block/blk-lib.c
@@ -338,3 +338,58 @@  int blkdev_issue_secure_erase(struct block_device *bdev, sector_t sector,
 	return ret;
 }
 EXPORT_SYMBOL(blkdev_issue_secure_erase);
+
+/**
+ * blkdev_issue_provision - provision a block range
+ * @bdev:	blockdev to write
+ * @sector:	start sector
+ * @nr_sects:	number of sectors to provision
+ * @gfp_mask:	memory allocation flags (for bio_alloc)
+ *
+ * Description:
+ *  Issues a provision request to the block device for the range of sectors.
+ *  For thinly provisioned block devices, this acts as a signal for the
+ *  underlying storage pool to allocate space for this block range.
+ */
+int blkdev_issue_provision(struct block_device *bdev, sector_t sector,
+		sector_t nr_sects, gfp_t gfp)
+{
+	sector_t bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
+	unsigned int max_sectors = bdev_max_provision_sectors(bdev);
+	struct bio *bio = NULL;
+	struct blk_plug plug;
+	int ret = 0;
+
+	if (max_sectors == 0)
+		return -EOPNOTSUPP;
+	if ((sector | nr_sects) & bs_mask)
+		return -EINVAL;
+	if (bdev_read_only(bdev))
+		return -EPERM;
+
+	blk_start_plug(&plug);
+	for (;;) {
+		unsigned int req_sects = min_t(sector_t, nr_sects, max_sectors);
+
+		bio = blk_next_bio(bio, bdev, 0, REQ_OP_PROVISION, gfp);
+		bio->bi_iter.bi_sector = sector;
+		bio->bi_iter.bi_size = req_sects << SECTOR_SHIFT;
+		bio_set_dev(bio, bdev);
+		bio_set_op_attrs(bio, REQ_OP_PROVISION, 0);
+
+		sector += req_sects;
+		nr_sects -= req_sects;
+		if (!nr_sects) {
+			ret = submit_bio_wait(bio);
+			if (ret == -EOPNOTSUPP)
+				ret = 0;
+			bio_put(bio);
+			break;
+		}
+		cond_resched();
+	}
+	blk_finish_plug(&plug);
+
+	return ret;
+}
+EXPORT_SYMBOL(blkdev_issue_provision);
diff --git a/block/blk-merge.c b/block/blk-merge.c
index ff04e9290715..ee8dd07b24fe 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -156,6 +156,20 @@  static struct bio *bio_split_write_zeroes(struct bio *bio,
 	return bio_split(bio, lim->max_write_zeroes_sectors, GFP_NOIO, bs);
 }
 
+static struct bio *bio_split_provision(struct bio *bio,
+		struct queue_limits *lim, unsigned *nsegs, struct bio_set *bs)
+{
+	*nsegs = 0;
+
+	if (!lim->max_provision_sectors)
+		return NULL;
+
+	if (bio_sectors(bio) <= lim->max_provision_sectors)
+		return NULL;
+
+	return bio_split(bio, lim->max_provision_sectors, GFP_NOIO, bs);
+}
+
 /*
  * Return the maximum number of sectors from the start of a bio that may be
  * submitted as a single request to a block device. If enough sectors remain,
@@ -345,6 +359,9 @@  struct bio *__bio_split_to_limits(struct bio *bio, struct queue_limits *lim,
 	case REQ_OP_WRITE_ZEROES:
 		split = bio_split_write_zeroes(bio, lim, nr_segs, bs);
 		break;
+	case REQ_OP_PROVISION:
+		split = bio_split_provision(bio, lim, nr_segs, bs);
+		break;
 	default:
 		split = bio_split_rw(bio, lim, nr_segs, bs,
 				get_max_io_size(bio, lim) << SECTOR_SHIFT);
diff --git a/block/blk-settings.c b/block/blk-settings.c
index 8bb9eef5310e..be79ad68b330 100644
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -57,6 +57,7 @@  void blk_set_default_limits(struct queue_limits *lim)
 	lim->misaligned = 0;
 	lim->zoned = BLK_ZONED_NONE;
 	lim->zone_write_granularity = 0;
+	lim->max_provision_sectors = 0;
 }
 EXPORT_SYMBOL(blk_set_default_limits);
 
@@ -81,6 +82,7 @@  void blk_set_stacking_limits(struct queue_limits *lim)
 	lim->max_dev_sectors = UINT_MAX;
 	lim->max_write_zeroes_sectors = UINT_MAX;
 	lim->max_zone_append_sectors = UINT_MAX;
+	lim->max_provision_sectors = UINT_MAX;
 }
 EXPORT_SYMBOL(blk_set_stacking_limits);
 
@@ -202,6 +204,20 @@  void blk_queue_max_write_zeroes_sectors(struct request_queue *q,
 }
 EXPORT_SYMBOL(blk_queue_max_write_zeroes_sectors);
 
+/**
+ * blk_queue_max_provision_sectors - set max sectors for a single provision
+ *
+ * @q:  the request queue for the device
+ * @max_provision_sectors: maximum number of sectors to provision per command
+ **/
+
+void blk_queue_max_provision_sectors(struct request_queue *q,
+		unsigned int max_provision_sectors)
+{
+	q->limits.max_provision_sectors = max_provision_sectors;
+}
+EXPORT_SYMBOL(blk_queue_max_provision_sectors);
+
 /**
  * blk_queue_max_zone_append_sectors - set max sectors for a single zone append
  * @q:  the request queue for the device
@@ -572,6 +588,9 @@  int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
 	t->max_segment_size = min_not_zero(t->max_segment_size,
 					   b->max_segment_size);
 
+	t->max_provision_sectors = min_not_zero(t->max_provision_sectors,
+						b->max_provision_sectors);
+
 	t->misaligned |= b->misaligned;
 
 	alignment = queue_limit_alignment_offset(b, start);
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index e1f009aba6fd..912159518322 100644
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c
@@ -131,6 +131,12 @@  static ssize_t queue_max_discard_segments_show(struct request_queue *q,
 	return queue_var_show(queue_max_discard_segments(q), page);
 }
 
+static ssize_t queue_max_provision_sectors_show(struct request_queue *q,
+		char *page)
+{
+	return queue_var_show(queue_max_provision_sectors(q), (page));
+}
+
 static ssize_t queue_max_integrity_segments_show(struct request_queue *q, char *page)
 {
 	return queue_var_show(q->limits.max_integrity_segments, page);
@@ -586,6 +592,7 @@  QUEUE_RO_ENTRY(queue_io_min, "minimum_io_size");
 QUEUE_RO_ENTRY(queue_io_opt, "optimal_io_size");
 
 QUEUE_RO_ENTRY(queue_max_discard_segments, "max_discard_segments");
+QUEUE_RO_ENTRY(queue_max_provision_sectors, "max_provision_sectors");
 QUEUE_RO_ENTRY(queue_discard_granularity, "discard_granularity");
 QUEUE_RO_ENTRY(queue_discard_max_hw, "discard_max_hw_bytes");
 QUEUE_RW_ENTRY(queue_discard_max, "discard_max_bytes");
@@ -635,6 +642,7 @@  static struct attribute *queue_attrs[] = {
 	&queue_max_sectors_entry.attr,
 	&queue_max_segments_entry.attr,
 	&queue_max_discard_segments_entry.attr,
+	&queue_max_provision_sectors_entry.attr,
 	&queue_max_integrity_segments_entry.attr,
 	&queue_max_segment_size_entry.attr,
 	&elv_iosched_entry.attr,
diff --git a/block/bounce.c b/block/bounce.c
index 7cfcb242f9a1..ab9d8723ae64 100644
--- a/block/bounce.c
+++ b/block/bounce.c
@@ -176,6 +176,7 @@  static struct bio *bounce_clone_bio(struct bio *bio_src)
 	case REQ_OP_DISCARD:
 	case REQ_OP_SECURE_ERASE:
 	case REQ_OP_WRITE_ZEROES:
+	case REQ_OP_PROVISION:
 		break;
 	default:
 		bio_for_each_segment(bv, bio_src, iter)
diff --git a/include/linux/bio.h b/include/linux/bio.h
index ca22b06700a9..3d5af770b90a 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -55,7 +55,8 @@  static inline bool bio_has_data(struct bio *bio)
 	    bio->bi_iter.bi_size &&
 	    bio_op(bio) != REQ_OP_DISCARD &&
 	    bio_op(bio) != REQ_OP_SECURE_ERASE &&
-	    bio_op(bio) != REQ_OP_WRITE_ZEROES)
+	    bio_op(bio) != REQ_OP_WRITE_ZEROES &&
+	    bio_op(bio) != REQ_OP_PROVISION)
 		return true;
 
 	return false;
@@ -65,7 +66,8 @@  static inline bool bio_no_advance_iter(const struct bio *bio)
 {
 	return bio_op(bio) == REQ_OP_DISCARD ||
 	       bio_op(bio) == REQ_OP_SECURE_ERASE ||
-	       bio_op(bio) == REQ_OP_WRITE_ZEROES;
+	       bio_op(bio) == REQ_OP_WRITE_ZEROES ||
+	       bio_op(bio) == REQ_OP_PROVISION;
 }
 
 static inline void *bio_data(struct bio *bio)
diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
index 1ef99790f6ed..c6e9823c1542 100644
--- a/include/linux/blk_types.h
+++ b/include/linux/blk_types.h
@@ -386,7 +386,10 @@  enum req_op {
 	REQ_OP_DRV_IN		= (__force blk_opf_t)34,
 	REQ_OP_DRV_OUT		= (__force blk_opf_t)35,
 
-	REQ_OP_LAST		= (__force blk_opf_t)36,
+	/* request device to provision block */
+	REQ_OP_PROVISION        = (__force blk_opf_t)37,
+
+	REQ_OP_LAST		= (__force blk_opf_t)38,
 };
 
 enum req_flag_bits {
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 84b13fdd34a7..a58496d3f922 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -302,6 +302,7 @@  struct queue_limits {
 	unsigned int		discard_granularity;
 	unsigned int		discard_alignment;
 	unsigned int		zone_write_granularity;
+	unsigned int		max_provision_sectors;
 
 	unsigned short		max_segments;
 	unsigned short		max_integrity_segments;
@@ -931,6 +932,8 @@  extern void blk_queue_max_discard_sectors(struct request_queue *q,
 		unsigned int max_discard_sectors);
 extern void blk_queue_max_write_zeroes_sectors(struct request_queue *q,
 		unsigned int max_write_same_sectors);
+extern void blk_queue_max_provision_sectors(struct request_queue *q,
+		unsigned int max_provision_sectors);
 extern void blk_queue_logical_block_size(struct request_queue *, unsigned int);
 extern void blk_queue_max_zone_append_sectors(struct request_queue *q,
 		unsigned int max_zone_append_sectors);
@@ -1071,6 +1074,9 @@  int __blkdev_issue_discard(struct block_device *bdev, sector_t sector,
 int blkdev_issue_secure_erase(struct block_device *bdev, sector_t sector,
 		sector_t nr_sects, gfp_t gfp);
 
+extern int blkdev_issue_provision(struct block_device *bdev, sector_t sector,
+		sector_t nr_sects, gfp_t gfp_mask);
+
 #define BLKDEV_ZERO_NOUNMAP	(1 << 0)  /* do not free blocks */
 #define BLKDEV_ZERO_NOFALLBACK	(1 << 1)  /* don't write explicit zeroes */
 
@@ -1149,6 +1155,11 @@  static inline unsigned short queue_max_discard_segments(const struct request_que
 	return q->limits.max_discard_segments;
 }
 
+static inline unsigned short queue_max_provision_sectors(const struct request_queue *q)
+{
+	return q->limits.max_provision_sectors;
+}
+
 static inline unsigned int queue_max_segment_size(const struct request_queue *q)
 {
 	return q->limits.max_segment_size;
@@ -1280,6 +1291,11 @@  static inline bool bdev_fua(struct block_device *bdev)
 	return test_bit(QUEUE_FLAG_FUA, &bdev_get_queue(bdev)->queue_flags);
 }
 
+static inline unsigned int bdev_max_provision_sectors(struct block_device *bdev)
+{
+	return bdev_get_queue(bdev)->limits.max_provision_sectors;
+}
+
 static inline enum blk_zoned_model bdev_zoned_model(struct block_device *bdev)
 {
 	struct request_queue *q = bdev_get_queue(bdev);