kernel/drivers/md/persistent-data/dm-space-map-metadata.c, branch linux-6.9.y

dm: add missing empty lines

2023-02-14T19:23:06Z

Signed-off-by: Heinz Mauelshagen Signed-off-by: Mike Snitzer

dm: change "unsigned" to "unsigned int"

2023-02-14T19:23:06Z

Signed-off-by: Heinz Mauelshagen Signed-off-by: Mike Snitzer

dm: add missing SPDX-License-Indentifiers

2023-02-14T19:23:06Z

'GPL-2.0-only' is used instead of 'GPL-2.0' because SPDX has deprecated its use. Suggested-by: John Wiele Signed-off-by: Heinz Mauelshagen Signed-off-by: Mike Snitzer

dm space maps: improve performance with inc/dec on ranges of blocks

2021-06-04T16:07:22Z

When we break sharing on btree nodes we typically need to increment the reference counts to every value held in the node. This can cause a lot of repeated calls to the space maps. Fix this by changing the interface to the space map inc/dec methods to take ranges of adjacent blocks to be operated on. For installations that are using a lot of snapshots this will reduce cpu overhead of fundamental operations such as provisioning a new block, or deleting a snapshot, by as much as 10 times. Signed-off-by: Joe Thornber Signed-off-by: Mike Snitzer

dm space maps: don't reset space map allocation cursor when committing

2021-06-04T16:07:21Z

Current commit code resets the place where the search for free blocks will begin back to the start of the metadata device. There are a couple of repercussions to this: - The first allocation after the commit is likely to take longer than normal as it searches for a free block in an area that is likely to have very few free blocks (if any). - Any free blocks it finds will have been recently freed. Reusing them means we have fewer old copies of the metadata to aid recovery from hardware error. Fix these issues by leaving the cursor alone, only resetting when the search hits the end of the metadata device. Signed-off-by: Joe Thornber Signed-off-by: Mike Snitzer

dm space map common: fix to ensure new block isn't already in use

2020-01-15T01:15:53Z

The space-maps track the reference counts for disk blocks allocated by both the thin-provisioning and cache targets. There are variants for tracking metadata blocks and data blocks. Transactionality is implemented by never touching blocks from the previous transaction, so we can rollback in the event of a crash. When allocating a new block we need to ensure the block is free (has reference count of 0) in both the current and previous transaction. Prior to this fix we were doing this by searching for a free block in the previous transaction, and relying on a 'begin' counter to track where the last allocation in the current transaction was. This 'begin' field was not being updated in all code paths (eg, increment of a data block reference count due to breaking sharing of a neighbour block in the same btree leaf). This fix keeps the 'begin' field, but now it's just a hint to speed up the search. Instead the current transaction is searched for a free block, and then the old transaction is double checked to ensure it's free. Much simpler. This fixes reports of sm_disk_new_block()'s BUG_ON() triggering when DM thin-provisioning's snapshots are heavily used. Reported-by: Eric Wheeler Cc: stable@vger.kernel.org Signed-off-by: Joe Thornber Signed-off-by: Mike Snitzer

dm space map metadata: fix missing store of apply_bops() return value

2019-08-22T20:11:24Z

In commit 6096d91af0b6 ("dm space map metadata: fix occasional leak of a metadata block on resize"), we refactor the commit logic to a new function 'apply_bops'. But when that logic was replaced in out() the return value was not stored. This may lead out() returning a wrong value to the caller. Fixes: 6096d91af0b6 ("dm space map metadata: fix occasional leak of a metadata block on resize") Cc: stable@vger.kernel.org Signed-off-by: ZhangXiaoxu Signed-off-by: Mike Snitzer

dm space map metadata: use ARRAY_SIZE

2017-11-10T20:44:52Z

Using the ARRAY_SIZE macro improves the readability of the code. Found with Coccinelle with the following semantic patch: @r depends on (org || report)@ type T; T[] E; position p; @@ ( (sizeof(E)@p /sizeof(*E)) | (sizeof(E)@p /sizeof(E[...])) | (sizeof(E)@p /sizeof(T)) ) Signed-off-by: Jérémy Lefaure Signed-off-by: Mike Snitzer

dm space map metadata: constify dm_space_map structures

2017-02-16T19:14:36Z

Declare dm_space_map structures as const as they are only passed as an argument to the function memcpy. This argument is of type const void *, so dm_space_map structures having this property can be declared as const. File size before: text data bss dec hex filename 4889 240 0 5129 1409 dm-space-map-metadata.o File size after: text data bss dec hex filename 5139 0 0 5139 1413 dm-space-map-metadata.o Signed-off-by: Bhumika Goyal Signed-off-by: Mike Snitzer

dm space map metadata: fix 'struct sm_metadata' leak on failed create

2016-12-08T19:13:14Z

In dm_sm_metadata_create() we temporarily change the dm_space_map operations from 'ops' (whose .destroy function deallocates the sm_metadata) to 'bootstrap_ops' (whose .destroy function doesn't). If dm_sm_metadata_create() fails in sm_ll_new_metadata() or sm_ll_extend(), it exits back to dm_tm_create_internal(), which calls dm_sm_destroy() with the intention of freeing the sm_metadata, but it doesn't (because the dm_space_map operations is still set to 'bootstrap_ops'). Fix this by setting the dm_space_map operations back to 'ops' if dm_sm_metadata_create() fails when it is set to 'bootstrap_ops'. Signed-off-by: Benjamin Marzinski Acked-by: Joe Thornber Signed-off-by: Mike Snitzer Cc: stable@vger.kernel.org