linux-dev - Linux kernel development work

Age	Commit message (Collapse)	Author	Files	Lines
2019-12-05	dm clone metadata: Use a two phase commit	Nikos Tsironis	1	-0/+17
	Split the metadata commit in two parts: 1. dm_clone_metadata_pre_commit(): Prepare the current transaction for committing. After this is called, all subsequent metadata updates, done through either dm_clone_set_region_hydrated() or dm_clone_cond_set_range(), will be part of the next transaction. 2. dm_clone_metadata_commit(): Actually commit the current transaction to disk and start a new transaction. This is required by the following commit. It allows dm-clone to flush the destination device after step (1) to ensure that all freshly hydrated regions, for which we are updating the metadata, are properly written to non-volatile storage and won't be lost in case of a crash. Fixes: 7431b7835f55 ("dm: add clone target") Cc: stable@vger.kernel.org # v5.4+ Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-11-05	dm clone: replace spin_lock_irqsave with spin_lock_irq	Mikulas Patocka	1	-1/+3
	If we are in a place where it is known that interrupts are enabled, functions spin_lock_irq/spin_unlock_irq should be used instead of spin_lock_irqsave/spin_unlock_irqrestore. spin_lock_irq and spin_unlock_irq are faster because they don't need to push and pop the flags register. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-09-12	dm: add clone target	Nikos Tsironis	1	-0/+158
	Add the dm-clone target, which allows cloning of arbitrary block devices. dm-clone produces a one-to-one copy of an existing, read-only source device into a writable destination device: It presents a virtual block device which makes all data appear immediately, and redirects reads and writes accordingly. The main use case of dm-clone is to clone a potentially remote, high-latency, read-only, archival-type block device into a writable, fast, primary-type device for fast, low-latency I/O. The cloned device is visible/mountable immediately and the copy of the source device to the destination device happens in the background, in parallel with user I/O. When the cloning completes, the dm-clone table can be removed altogether and be replaced, e.g., by a linear table, mapping directly to the destination device. For further information and examples of how to use dm-clone, please read Documentation/admin-guide/device-mapper/dm-clone.rst Suggested-by: Vangelis Koukis <vkoukis@arrikto.com> Co-developed-by: Ilias Tsitsimpis <iliastsi@arrikto.com> Signed-off-by: Ilias Tsitsimpis <iliastsi@arrikto.com> Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>