diff mbox series

[2/2] btrfs: Use btrfs_io_geometry appropriately

Message ID 20190531150115.21003-2-nborisov@suse.com (mailing list archive)
State New, archived
Headers show
Series [1/2] btrfs: Introduce btrfs_io_geometry | expand

Commit Message

Nikolay Borisov May 31, 2019, 3:01 p.m. UTC 
Presently btrfs_map_block is used not only to do everything necessary
to map a bio to the underlying allocation profile but it's also used to
identify how much data could be written based on btrfs' stripe logic
without actually submitting anything. This is achieved by passing NULL
for 'bbio_ret' parameter.

This patch refactors all callers that require just the mapping length
by switching them to using btrfs_io_geometry instead of calling
btrfs_map_block with a special NULL value for 'bbio_ret'. No functional
change.
---
 fs/btrfs/inode.c   | 25 +++++++--------
 fs/btrfs/volumes.c | 77 +++++++++-------------------------------------
 2 files changed, 27 insertions(+), 75 deletions(-)
diff mbox series

Patch

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 80fdf6f21f74..a3abba4c2e2c 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -1932,17 +1932,19 @@  int btrfs_bio_fits_in_stripe(struct page *page, size_t size, struct bio *bio,
 	u64 length = 0;
 	u64 map_length;
 	int ret;
+	struct btrfs_io_geometry geom;
 
 	if (bio_flags & EXTENT_BIO_COMPRESSED)
 		return 0;
 
 	length = bio->bi_iter.bi_size;
 	map_length = length;
-	ret = btrfs_map_block(fs_info, btrfs_op(bio), logical, &map_length,
-			      NULL, 0);
+	ret = btrfs_io_geometry(fs_info, btrfs_op(bio), logical, map_length,
+				&geom);
 	if (ret < 0)
 		return ret;
-	if (map_length < length + size)
+
+	if (geom.len < length + size)
 		return 1;
 	return 0;
 }
@@ -8331,15 +8333,15 @@  static int btrfs_submit_direct_hook(struct btrfs_dio_private *dip)
 	int clone_len;
 	int ret;
 	blk_status_t status;
+	struct btrfs_io_geometry geom;
 
-	map_length = orig_bio->bi_iter.bi_size;
-	submit_len = map_length;
-	ret = btrfs_map_block(fs_info, btrfs_op(orig_bio), start_sector << 9,
-			      &map_length, NULL, 0);
+	submit_len = orig_bio->bi_iter.bi_size;
+	ret = btrfs_io_geometry(fs_info, btrfs_op(orig_bio), start_sector << 9,
+			      submit_len, &geom);
 	if (ret)
 		return -EIO;
 
-	map_length = min_t(u64, map_length, SZ_1M);
+	map_length = min_t(u64, geom.len, SZ_1M);
 	if (map_length >= submit_len) {
 		bio = orig_bio;
 		dip->flags |= BTRFS_DIO_ORIG_BIO_SUBMITTED;
@@ -8393,13 +8395,12 @@  static int btrfs_submit_direct_hook(struct btrfs_dio_private *dip)
 		start_sector += clone_len >> 9;
 		file_offset += clone_len;
 
-		map_length = submit_len;
-		ret = btrfs_map_block(fs_info, btrfs_op(orig_bio),
-				      start_sector << 9, &map_length, NULL, 0);
+		ret = btrfs_io_geometry(fs_info, btrfs_op(orig_bio),
+				      start_sector << 9, submit_len, &geom);
 		if (ret)
 			goto out_err;
 
-		map_length = min_t(u64, map_length, SZ_1M);
+		map_length = min_t(u64, geom.len, SZ_1M);
 	} while (submit_len > 0);
 
 submit:
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index b130f465ca6d..9d9d1d3329bb 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -5961,7 +5961,6 @@  int btrfs_io_geometry(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
 	stripe_offset = offset - stripe_offset;
 	data_stripes = nr_data_stripes(map);
 
-
 	if (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
 		u64 max_len = stripe_len - stripe_offset;
 
@@ -6031,78 +6030,30 @@  static int __btrfs_map_block(struct btrfs_fs_info *fs_info,
 	int patch_the_first_stripe_for_dev_replace = 0;
 	u64 physical_to_patch_in_first_stripe = 0;
 	u64 raid56_full_stripe_start = (u64)-1;
+	struct btrfs_io_geometry geom;
+
+	ASSERT(bbio_ret);
 
 	if (op == BTRFS_MAP_DISCARD)
 		return __btrfs_map_block_for_discard(fs_info, logical,
 						     *length, bbio_ret);
 
-	em = btrfs_get_chunk_map(fs_info, logical, *length);
-	if (IS_ERR(em))
-		return PTR_ERR(em);
+	ret = btrfs_io_geometry(fs_info, op, logical, *length, &geom);
+	if (ret < 0)
+		return ret;
 
+	em = btrfs_get_chunk_map(fs_info, logical, *length);
+	ASSERT(em);
 	map = em->map_lookup;
-	offset = logical - em->start;
 
-	stripe_len = map->stripe_len;
-	stripe_nr = offset;
-	/*
-	 * stripe_nr counts the total number of stripes we have to stride
-	 * to get to this block
-	 */
-	stripe_nr = div64_u64(stripe_nr, stripe_len);
+	*length = geom.len;
+	offset = geom.offset;
+	stripe_len = geom.stripe_len;
+	stripe_nr = geom.stripe_nr;
+	stripe_offset = geom.stripe_offset;
+	raid56_full_stripe_start = geom.raid56_stripe_offset;
 	data_stripes = nr_data_stripes(map);
 
-	stripe_offset = stripe_nr * stripe_len;
-	if (offset < stripe_offset) {
-		btrfs_crit(fs_info,
-			   "stripe math has gone wrong, stripe_offset=%llu, offset=%llu, start=%llu, logical=%llu, stripe_len=%llu",
-			   stripe_offset, offset, em->start, logical,
-			   stripe_len);
-		free_extent_map(em);
-		return -EINVAL;
-	}
-
-	/* stripe_offset is the offset of this block in its stripe*/
-	stripe_offset = offset - stripe_offset;
-
-	/* if we're here for raid56, we need to know the stripe aligned start */
-	if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
-		unsigned long full_stripe_len = stripe_len * data_stripes;
-		raid56_full_stripe_start = offset;
-
-		/* allow a write of a full stripe, but make sure we don't
-		 * allow straddling of stripes
-		 */
-		raid56_full_stripe_start = div64_u64(raid56_full_stripe_start,
-				full_stripe_len);
-		raid56_full_stripe_start *= full_stripe_len;
-	}
-
-	if (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
-		u64 max_len;
-		/* For writes to RAID[56], allow a full stripeset across all disks.
-		   For other RAID types and for RAID[56] reads, just allow a single
-		   stripe (on a single disk). */
-		if ((map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) &&
-		    (op == BTRFS_MAP_WRITE)) {
-			max_len = stripe_len * data_stripes -
-				(offset - raid56_full_stripe_start);
-		} else {
-			/* we limit the length of each bio to what fits in a stripe */
-			max_len = stripe_len - stripe_offset;
-		}
-		*length = min_t(u64, em->len - offset, max_len);
-	} else {
-		*length = em->len - offset;
-	}
-
-	/*
-	 * This is for when we're called from btrfs_bio_fits_in_stripe and all
-	 * it cares about is the length
-	 */
-	if (!bbio_ret)
-		goto out;
-
 	down_read(&dev_replace->rwsem);
 	dev_replace_is_ongoing = btrfs_dev_replace_is_ongoing(dev_replace);
 	/*