Merge branch 'for-4.5/drivers' of git://git.kernel.dk/linux-block

Pull block driver updates from Jens Axboe:
 "This is the block driver pull request for 4.5, with the exception of
  NVMe, which is in a separate branch and will be posted after this one.

  This pull request contains:

   - A set of bcache stability fixes, which have been acked by Kent.
     These have been used and tested for more than a year by the
     community, so it's about time that they got in.

   - A set of drbd updates from the drbd team (Andreas, Lars, Philipp)
     and Markus Elfring, Oleg Drokin.

   - A set of fixes for xen blkback/front from the usual suspects, (Bob,
     Konrad) as well as community based fixes from Kiri, Julien, and
     Peng.

   - A 2038 time fix for sx8 from Shraddha, with a fix from me.

   - A small mtip32xx cleanup from Zhu Yanjun.

   - A null_blk division fix from Arnd"

* 'for-4.5/drivers' of git://git.kernel.dk/linux-block: (71 commits)
  null_blk: use sector_div instead of do_div
  mtip32xx: restrict variables visible in current code module
  xen/blkfront: Fix crash if backend doesn't follow the right states.
  xen/blkback: Fix two memory leaks.
  xen/blkback: make st_ statistics per ring
  xen/blkfront: Handle non-indirect grant with 64KB pages
  xen-blkfront: Introduce blkif_ring_get_request
  xen-blkback: clear PF_NOFREEZE for xen_blkif_schedule()
  xen/blkback: Free resources if connect_ring failed.
  xen/blocks: Return -EXX instead of -1
  xen/blkback: make pool of persistent grants and free pages per-queue
  xen/blkback: get the number of hardware queues/rings from blkfront
  xen/blkback: pseudo support for multi hardware queues/rings
  xen/blkback: separate ring information out of struct xen_blkif
  xen/blkfront: correct setting for xen_blkif_max_ring_order
  xen/blkfront: make persistent grants pool per-queue
  xen/blkfront: Remove duplicate setting of ->xbdev.
  xen/blkfront: Cleanup of comments, fix unaligned variables, and syntax errors.
  xen/blkfront: negotiate number of queues/rings to be used with backend
  xen/blkfront: split per device io_lock
  ...

Author: torvalds

MAINTAINERS

@@ -3665,13 +3665,12 @@ F:	drivers/scsi/dpt*
 F:	drivers/scsi/dpt/
 
 DRBD DRIVER
-P:	Philipp Reisner
-P:	Lars Ellenberg
-M:	[email protected]
-L:	[email protected]
+M:	Philipp Reisner <[email protected]>
+M:	Lars Ellenberg <[email protected]>
+L:	[email protected]
 W:	http://www.drbd.org
-T:	git git://git.drbd.org/linux-2.6-drbd.git drbd
-T:	git git://git.drbd.org/drbd-8.3.git
+T:	git git://git.linbit.com/linux-drbd.git
+T:	git git://git.linbit.com/drbd-8.4.git
 S:	Supported
 F:	drivers/block/drbd/
 F:	lib/lru_cache.c

drivers/block/drbd/drbd_actlog.c

@@ -288,7 +288,162 @@ bool drbd_al_begin_io_prepare(struct drbd_device *device, struct drbd_interval *
 	return need_transaction;
 }
 
-static int al_write_transaction(struct drbd_device *device);
+#if (PAGE_SHIFT + 3) < (AL_EXTENT_SHIFT - BM_BLOCK_SHIFT)
+/* Currently BM_BLOCK_SHIFT, BM_EXT_SHIFT and AL_EXTENT_SHIFT
+ * are still coupled, or assume too much about their relation.
+ * Code below will not work if this is violated.
+ * Will be cleaned up with some followup patch.
+ */
+# error FIXME
+#endif
+
+static unsigned int al_extent_to_bm_page(unsigned int al_enr)
+{
+	return al_enr >>
+		/* bit to page */
+		((PAGE_SHIFT + 3) -
+		/* al extent number to bit */
+		 (AL_EXTENT_SHIFT - BM_BLOCK_SHIFT));
+}
+
+static sector_t al_tr_number_to_on_disk_sector(struct drbd_device *device)
+{
+	const unsigned int stripes = device->ldev->md.al_stripes;
+	const unsigned int stripe_size_4kB = device->ldev->md.al_stripe_size_4k;
+
+	/* transaction number, modulo on-disk ring buffer wrap around */
+	unsigned int t = device->al_tr_number % (device->ldev->md.al_size_4k);
+
+	/* ... to aligned 4k on disk block */
+	t = ((t % stripes) * stripe_size_4kB) + t/stripes;
+
+	/* ... to 512 byte sector in activity log */
+	t *= 8;
+
+	/* ... plus offset to the on disk position */
+	return device->ldev->md.md_offset + device->ldev->md.al_offset + t;
+}
+
+static int __al_write_transaction(struct drbd_device *device, struct al_transaction_on_disk *buffer)
+{
+	struct lc_element *e;
+	sector_t sector;
+	int i, mx;
+	unsigned extent_nr;
+	unsigned crc = 0;
+	int err = 0;
+
+	memset(buffer, 0, sizeof(*buffer));
+	buffer->magic = cpu_to_be32(DRBD_AL_MAGIC);
+	buffer->tr_number = cpu_to_be32(device->al_tr_number);
+
+	i = 0;
+
+	/* Even though no one can start to change this list
+	 * once we set the LC_LOCKED -- from drbd_al_begin_io(),
+	 * lc_try_lock_for_transaction() --, someone may still
+	 * be in the process of changing it. */
+	spin_lock_irq(&device->al_lock);
+	list_for_each_entry(e, &device->act_log->to_be_changed, list) {
+		if (i == AL_UPDATES_PER_TRANSACTION) {
+			i++;
+			break;
+		}
+		buffer->update_slot_nr[i] = cpu_to_be16(e->lc_index);
+		buffer->update_extent_nr[i] = cpu_to_be32(e->lc_new_number);
+		if (e->lc_number != LC_FREE)
+			drbd_bm_mark_for_writeout(device,
+					al_extent_to_bm_page(e->lc_number));
+		i++;
+	}
+	spin_unlock_irq(&device->al_lock);
+	BUG_ON(i > AL_UPDATES_PER_TRANSACTION);
+
+	buffer->n_updates = cpu_to_be16(i);
+	for ( ; i < AL_UPDATES_PER_TRANSACTION; i++) {
+		buffer->update_slot_nr[i] = cpu_to_be16(-1);
+		buffer->update_extent_nr[i] = cpu_to_be32(LC_FREE);
+	}
+
+	buffer->context_size = cpu_to_be16(device->act_log->nr_elements);
+	buffer->context_start_slot_nr = cpu_to_be16(device->al_tr_cycle);
+
+	mx = min_t(int, AL_CONTEXT_PER_TRANSACTION,
+		   device->act_log->nr_elements - device->al_tr_cycle);
+	for (i = 0; i < mx; i++) {
+		unsigned idx = device->al_tr_cycle + i;
+		extent_nr = lc_element_by_index(device->act_log, idx)->lc_number;
+		buffer->context[i] = cpu_to_be32(extent_nr);
+	}
+	for (; i < AL_CONTEXT_PER_TRANSACTION; i++)
+		buffer->context[i] = cpu_to_be32(LC_FREE);
+
+	device->al_tr_cycle += AL_CONTEXT_PER_TRANSACTION;
+	if (device->al_tr_cycle >= device->act_log->nr_elements)
+		device->al_tr_cycle = 0;
+
+	sector = al_tr_number_to_on_disk_sector(device);
+
+	crc = crc32c(0, buffer, 4096);
+	buffer->crc32c = cpu_to_be32(crc);
+
+	if (drbd_bm_write_hinted(device))
+		err = -EIO;
+	else {
+		bool write_al_updates;
+		rcu_read_lock();
+		write_al_updates = rcu_dereference(device->ldev->disk_conf)->al_updates;
+		rcu_read_unlock();
+		if (write_al_updates) {
+			if (drbd_md_sync_page_io(device, device->ldev, sector, WRITE)) {
+				err = -EIO;
+				drbd_chk_io_error(device, 1, DRBD_META_IO_ERROR);
+			} else {
+				device->al_tr_number++;
+				device->al_writ_cnt++;
+			}
+		}
+	}
+
+	return err;
+}
+
+static int al_write_transaction(struct drbd_device *device)
+{
+	struct al_transaction_on_disk *buffer;
+	int err;
+
+	if (!get_ldev(device)) {
+		drbd_err(device, "disk is %s, cannot start al transaction\n",
+			drbd_disk_str(device->state.disk));
+		return -EIO;
+	}
+
+	/* The bitmap write may have failed, causing a state change. */
+	if (device->state.disk < D_INCONSISTENT) {
+		drbd_err(device,
+			"disk is %s, cannot write al transaction\n",
+			drbd_disk_str(device->state.disk));
+		put_ldev(device);
+		return -EIO;
+	}
+
+	/* protects md_io_buffer, al_tr_cycle, ... */
+	buffer = drbd_md_get_buffer(device, __func__);
+	if (!buffer) {
+		drbd_err(device, "disk failed while waiting for md_io buffer\n");
+		put_ldev(device);
+		return -ENODEV;
+	}
+
+	err = __al_write_transaction(device, buffer);
+
+	drbd_md_put_buffer(device);
+	put_ldev(device);
+
+	return err;
+}
+
 
 void drbd_al_begin_io_commit(struct drbd_device *device)
 {
@@ -420,153 +575,6 @@ void drbd_al_complete_io(struct drbd_device *device, struct drbd_interval *i)
 	wake_up(&device->al_wait);
 }
 
-#if (PAGE_SHIFT + 3) < (AL_EXTENT_SHIFT - BM_BLOCK_SHIFT)
-/* Currently BM_BLOCK_SHIFT, BM_EXT_SHIFT and AL_EXTENT_SHIFT
- * are still coupled, or assume too much about their relation.
- * Code below will not work if this is violated.
- * Will be cleaned up with some followup patch.
- */
-# error FIXME
-#endif
-
-static unsigned int al_extent_to_bm_page(unsigned int al_enr)
-{
-	return al_enr >>
-		/* bit to page */
-		((PAGE_SHIFT + 3) -
-		/* al extent number to bit */
-		 (AL_EXTENT_SHIFT - BM_BLOCK_SHIFT));
-}
-
-static sector_t al_tr_number_to_on_disk_sector(struct drbd_device *device)
-{
-	const unsigned int stripes = device->ldev->md.al_stripes;
-	const unsigned int stripe_size_4kB = device->ldev->md.al_stripe_size_4k;
-
-	/* transaction number, modulo on-disk ring buffer wrap around */
-	unsigned int t = device->al_tr_number % (device->ldev->md.al_size_4k);
-
-	/* ... to aligned 4k on disk block */
-	t = ((t % stripes) * stripe_size_4kB) + t/stripes;
-
-	/* ... to 512 byte sector in activity log */
-	t *= 8;
-
-	/* ... plus offset to the on disk position */
-	return device->ldev->md.md_offset + device->ldev->md.al_offset + t;
-}
-
-int al_write_transaction(struct drbd_device *device)
-{
-	struct al_transaction_on_disk *buffer;
-	struct lc_element *e;
-	sector_t sector;
-	int i, mx;
-	unsigned extent_nr;
-	unsigned crc = 0;
-	int err = 0;
-
-	if (!get_ldev(device)) {
-		drbd_err(device, "disk is %s, cannot start al transaction\n",
-			drbd_disk_str(device->state.disk));
-		return -EIO;
-	}
-
-	/* The bitmap write may have failed, causing a state change. */
-	if (device->state.disk < D_INCONSISTENT) {
-		drbd_err(device,
-			"disk is %s, cannot write al transaction\n",
-			drbd_disk_str(device->state.disk));
-		put_ldev(device);
-		return -EIO;
-	}
-
-	/* protects md_io_buffer, al_tr_cycle, ... */
-	buffer = drbd_md_get_buffer(device, __func__);
-	if (!buffer) {
-		drbd_err(device, "disk failed while waiting for md_io buffer\n");
-		put_ldev(device);
-		return -ENODEV;
-	}
-
-	memset(buffer, 0, sizeof(*buffer));
-	buffer->magic = cpu_to_be32(DRBD_AL_MAGIC);
-	buffer->tr_number = cpu_to_be32(device->al_tr_number);
-
-	i = 0;
-
-	/* Even though no one can start to change this list
-	 * once we set the LC_LOCKED -- from drbd_al_begin_io(),
-	 * lc_try_lock_for_transaction() --, someone may still
-	 * be in the process of changing it. */
-	spin_lock_irq(&device->al_lock);
-	list_for_each_entry(e, &device->act_log->to_be_changed, list) {
-		if (i == AL_UPDATES_PER_TRANSACTION) {
-			i++;
-			break;
-		}
-		buffer->update_slot_nr[i] = cpu_to_be16(e->lc_index);
-		buffer->update_extent_nr[i] = cpu_to_be32(e->lc_new_number);
-		if (e->lc_number != LC_FREE)
-			drbd_bm_mark_for_writeout(device,
-					al_extent_to_bm_page(e->lc_number));
-		i++;
-	}
-	spin_unlock_irq(&device->al_lock);
-	BUG_ON(i > AL_UPDATES_PER_TRANSACTION);
-
-	buffer->n_updates = cpu_to_be16(i);
-	for ( ; i < AL_UPDATES_PER_TRANSACTION; i++) {
-		buffer->update_slot_nr[i] = cpu_to_be16(-1);
-		buffer->update_extent_nr[i] = cpu_to_be32(LC_FREE);
-	}
-
-	buffer->context_size = cpu_to_be16(device->act_log->nr_elements);
-	buffer->context_start_slot_nr = cpu_to_be16(device->al_tr_cycle);
-
-	mx = min_t(int, AL_CONTEXT_PER_TRANSACTION,
-		   device->act_log->nr_elements - device->al_tr_cycle);
-	for (i = 0; i < mx; i++) {
-		unsigned idx = device->al_tr_cycle + i;
-		extent_nr = lc_element_by_index(device->act_log, idx)->lc_number;
-		buffer->context[i] = cpu_to_be32(extent_nr);
-	}
-	for (; i < AL_CONTEXT_PER_TRANSACTION; i++)
-		buffer->context[i] = cpu_to_be32(LC_FREE);
-
-	device->al_tr_cycle += AL_CONTEXT_PER_TRANSACTION;
-	if (device->al_tr_cycle >= device->act_log->nr_elements)
-		device->al_tr_cycle = 0;
-
-	sector = al_tr_number_to_on_disk_sector(device);
-
-	crc = crc32c(0, buffer, 4096);
-	buffer->crc32c = cpu_to_be32(crc);
-
-	if (drbd_bm_write_hinted(device))
-		err = -EIO;
-	else {
-		bool write_al_updates;
-		rcu_read_lock();
-		write_al_updates = rcu_dereference(device->ldev->disk_conf)->al_updates;
-		rcu_read_unlock();
-		if (write_al_updates) {
-			if (drbd_md_sync_page_io(device, device->ldev, sector, WRITE)) {
-				err = -EIO;
-				drbd_chk_io_error(device, 1, DRBD_META_IO_ERROR);
-			} else {
-				device->al_tr_number++;
-				device->al_writ_cnt++;
-			}
-		}
-	}
-
-	drbd_md_put_buffer(device);
-	put_ldev(device);
-
-	return err;
-}
-
 static int _try_lc_del(struct drbd_device *device, struct lc_element *al_ext)
 {
 	int rv;
@@ -606,21 +614,24 @@ void drbd_al_shrink(struct drbd_device *device)
 	wake_up(&device->al_wait);
 }
 
-int drbd_initialize_al(struct drbd_device *device, void *buffer)
+int drbd_al_initialize(struct drbd_device *device, void *buffer)
 {
 	struct al_transaction_on_disk *al = buffer;
 	struct drbd_md *md = &device->ldev->md;
-	sector_t al_base = md->md_offset + md->al_offset;
 	int al_size_4k = md->al_stripes * md->al_stripe_size_4k;
 	int i;
 
-	memset(al, 0, 4096);
-	al->magic = cpu_to_be32(DRBD_AL_MAGIC);
-	al->transaction_type = cpu_to_be16(AL_TR_INITIALIZED);
-	al->crc32c = cpu_to_be32(crc32c(0, al, 4096));
+	__al_write_transaction(device, al);
+	/* There may or may not have been a pending transaction. */
+	spin_lock_irq(&device->al_lock);
+	lc_committed(device->act_log);
+	spin_unlock_irq(&device->al_lock);
 
-	for (i = 0; i < al_size_4k; i++) {
-		int err = drbd_md_sync_page_io(device, device->ldev, al_base + i * 8, WRITE);
+	/* The rest of the transactions will have an empty "updates" list, and
+	 * are written out only to provide the context, and to initialize the
+	 * on-disk ring buffer. */
+	for (i = 1; i < al_size_4k; i++) {
+		int err = __al_write_transaction(device, al);
 		if (err)
 			return err;
 	}