Merge tag 'dm-3.16-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper updates from Mike Snitzer:
 "This pull request is later than I'd have liked because I was waiting
  for some performance data to help finally justify sending the
  long-standing dm-crypt cpu scalability improvements upstream.

  Unfortunately we came up short, so those dm-crypt changes will
  continue to wait, but it seems we're not far off.

   . Add dm_accept_partial_bio interface to DM core to allow DM targets
     to only process a portion of a bio, the remainder being sent in the
     next bio.  This enables the old dm snapshot-origin target to only
     split write bios on chunk boundaries, read bios are now sent to the
     origin device unchanged.

   . Add DM core support for disabling WRITE SAME if the underlying SCSI
     layer disables it due to command failure.

   . Reduce lock contention in DM's bio-prison.

   . A few small cleanups and fixes to dm-thin and dm-era"

* tag 'dm-3.16-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm thin: update discard_granularity to reflect the thin-pool blocksize
  dm bio prison: implement per bucket locking in the dm_bio_prison hash table
  dm: remove symbol export for dm_set_device_limits
  dm: disable WRITE SAME if it fails
  dm era: check for a non-NULL metadata object before closing it
  dm thin: return ENOSPC instead of EIO when error_if_no_space enabled
  dm thin: cleanup noflush_work to use a proper completion
  dm snapshot: do not split read bios sent to snapshot-origin target
  dm snapshot: allocate a per-target structure for snapshot-origin target
  dm: introduce dm_accept_partial_bio
  dm: change sector_count member in clone_info from sector_t to unsigned
This commit is contained in:
Linus Torvalds
2014-06-12 13:33:29 -07:00
9 changed files with 233 additions and 120 deletions

View File

@@ -2141,6 +2141,11 @@ static int origin_write_extent(struct dm_snapshot *merging_snap,
* Origin: maps a linear range of a device, with hooks for snapshotting.
*/
struct dm_origin {
struct dm_dev *dev;
unsigned split_boundary;
};
/*
* Construct an origin mapping: <dev_path>
* The context for an origin is merely a 'struct dm_dev *'
@@ -2149,41 +2154,65 @@ static int origin_write_extent(struct dm_snapshot *merging_snap,
static int origin_ctr(struct dm_target *ti, unsigned int argc, char **argv)
{
int r;
struct dm_dev *dev;
struct dm_origin *o;
if (argc != 1) {
ti->error = "origin: incorrect number of arguments";
return -EINVAL;
}
r = dm_get_device(ti, argv[0], dm_table_get_mode(ti->table), &dev);
if (r) {
ti->error = "Cannot get target device";
return r;
o = kmalloc(sizeof(struct dm_origin), GFP_KERNEL);
if (!o) {
ti->error = "Cannot allocate private origin structure";
r = -ENOMEM;
goto bad_alloc;
}
ti->private = dev;
r = dm_get_device(ti, argv[0], dm_table_get_mode(ti->table), &o->dev);
if (r) {
ti->error = "Cannot get target device";
goto bad_open;
}
ti->private = o;
ti->num_flush_bios = 1;
return 0;
bad_open:
kfree(o);
bad_alloc:
return r;
}
static void origin_dtr(struct dm_target *ti)
{
struct dm_dev *dev = ti->private;
dm_put_device(ti, dev);
struct dm_origin *o = ti->private;
dm_put_device(ti, o->dev);
kfree(o);
}
static int origin_map(struct dm_target *ti, struct bio *bio)
{
struct dm_dev *dev = ti->private;
bio->bi_bdev = dev->bdev;
struct dm_origin *o = ti->private;
unsigned available_sectors;
if (bio->bi_rw & REQ_FLUSH)
bio->bi_bdev = o->dev->bdev;
if (unlikely(bio->bi_rw & REQ_FLUSH))
return DM_MAPIO_REMAPPED;
if (bio_rw(bio) != WRITE)
return DM_MAPIO_REMAPPED;
available_sectors = o->split_boundary -
((unsigned)bio->bi_iter.bi_sector & (o->split_boundary - 1));
if (bio_sectors(bio) > available_sectors)
dm_accept_partial_bio(bio, available_sectors);
/* Only tell snapshots if this is a write */
return (bio_rw(bio) == WRITE) ? do_origin(dev, bio) : DM_MAPIO_REMAPPED;
return do_origin(o->dev, bio);
}
/*
@@ -2192,15 +2221,15 @@ static int origin_map(struct dm_target *ti, struct bio *bio)
*/
static void origin_resume(struct dm_target *ti)
{
struct dm_dev *dev = ti->private;
struct dm_origin *o = ti->private;
ti->max_io_len = get_origin_minimum_chunksize(dev->bdev);
o->split_boundary = get_origin_minimum_chunksize(o->dev->bdev);
}
static void origin_status(struct dm_target *ti, status_type_t type,
unsigned status_flags, char *result, unsigned maxlen)
{
struct dm_dev *dev = ti->private;
struct dm_origin *o = ti->private;
switch (type) {
case STATUSTYPE_INFO:
@@ -2208,7 +2237,7 @@ static void origin_status(struct dm_target *ti, status_type_t type,
break;
case STATUSTYPE_TABLE:
snprintf(result, maxlen, "%s", dev->name);
snprintf(result, maxlen, "%s", o->dev->name);
break;
}
}
@@ -2216,13 +2245,13 @@ static void origin_status(struct dm_target *ti, status_type_t type,
static int origin_merge(struct dm_target *ti, struct bvec_merge_data *bvm,
struct bio_vec *biovec, int max_size)
{
struct dm_dev *dev = ti->private;
struct request_queue *q = bdev_get_queue(dev->bdev);
struct dm_origin *o = ti->private;
struct request_queue *q = bdev_get_queue(o->dev->bdev);
if (!q->merge_bvec_fn)
return max_size;
bvm->bi_bdev = dev->bdev;
bvm->bi_bdev = o->dev->bdev;
return min(max_size, q->merge_bvec_fn(q, bvm, biovec));
}
@@ -2230,9 +2259,9 @@ static int origin_merge(struct dm_target *ti, struct bvec_merge_data *bvm,
static int origin_iterate_devices(struct dm_target *ti,
iterate_devices_callout_fn fn, void *data)
{
struct dm_dev *dev = ti->private;
struct dm_origin *o = ti->private;
return fn(ti, dev, 0, ti->len, data);
return fn(ti, o->dev, 0, ti->len, data);
}
static struct target_type origin_target = {