tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
dm: linear add merge
This patch implements biovec merge function for linear target.
If the underlying device has merge function defined, call it.
If not, keep precomputed value.
Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
authored by
Milan Broz
and committed by
Alasdair G Kergon
7bc3447b
f6fccb12
+33
-5
+33
-5
drivers/md/dm-linear.c
+33
-5
drivers/md/dm-linear.c
···
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kfree(lc);
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}
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static sector_t linear_map_sector(struct dm_target *ti, sector_t bi_sector)
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{
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struct linear_c *lc = ti->private;
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+
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return lc->start + (bi_sector - ti->begin);
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}
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static void linear_map_bio(struct dm_target *ti, struct bio *bio)
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{
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struct linear_c *lc = ti->private;
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bio->bi_bdev = lc->dev->bdev;
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bio->bi_sector = linear_map_sector(ti, bio->bi_sector);
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}
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static int linear_map(struct dm_target *ti, struct bio *bio,
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union map_info *map_context)
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{
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struct linear_c *lc = (struct linear_c *) ti->private;
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bio->bi_bdev = lc->dev->bdev;
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bio->bi_sector = lc->start + (bio->bi_sector - ti->begin);
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linear_map_bio(ti, bio);
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return DM_MAPIO_REMAPPED;
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}
···
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return blkdev_driver_ioctl(bdev->bd_inode, &fake_file, bdev->bd_disk, cmd, arg);
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}
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static int linear_merge(struct dm_target *ti, struct bvec_merge_data *bvm,
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struct bio_vec *biovec, int max_size)
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{
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struct linear_c *lc = ti->private;
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struct request_queue *q = bdev_get_queue(lc->dev->bdev);
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if (!q->merge_bvec_fn)
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return max_size;
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bvm->bi_bdev = lc->dev->bdev;
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bvm->bi_sector = linear_map_sector(ti, bvm->bi_sector);
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return min(max_size, q->merge_bvec_fn(q, bvm, biovec));
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}
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static struct target_type linear_target = {
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.name = "linear",
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.version= {1, 0, 2},
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.version= {1, 0, 3},
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.module = THIS_MODULE,
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.ctr = linear_ctr,
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.dtr = linear_dtr,
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.map = linear_map,
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.status = linear_status,
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.ioctl = linear_ioctl,
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.merge = linear_merge,
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};
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int __init dm_linear_init(void)