linux-dev/drivers/md/persistent-data, branch linus/master

dm space map common: add bounds check to sm_ll_lookup_bitmap()

2022-01-04T18:58:19Z

Corrupted metadata could warrant returning error from sm_ll_lookup_bitmap(). Signed-off-by: Joe Thornber Signed-off-by: Mike Snitzer

dm btree: add a defensive bounds check to insert_at()

2022-01-04T18:56:03Z

Corrupt metadata could trigger an out of bounds write. Signed-off-by: Joe Thornber Signed-off-by: Mike Snitzer

dm btree remove: change a bunch of BUG_ON() calls to proper errors

2022-01-04T18:48:12Z

Abuse of BUG_ON() is never appropriate, best to propagate errors to fail gracefully (rather than take the entire system down). Signed-off-by: Joe Thornber Signed-off-by: Mike Snitzer

dm btree spine: eliminate duplicate le32_to_cpu() in node_check()

2022-01-04T17:59:55Z

Signed-off-by: Joe Thornber Signed-off-by: Mike Snitzer

dm btree spine: remove extra node_check function declaration

2022-01-04T17:52:08Z

Should have been removed as part of commit f73e2e70ec48 ("dm btree spine: remove paranoid node_check call in node_prep_for_write()") Signed-off-by: Joe Thornber Signed-off-by: Mike Snitzer

dm btree remove: fix use after free in rebalance_children()

2021-11-24T17:07:39Z

Move dm_tm_unlock() after dm_tm_dec(). Cc: stable@vger.kernel.org Signed-off-by: Joe Thornber Signed-off-by: Mike Snitzer

dm btree remove: assign new_root only when removal succeeds

2021-06-25T19:25:24Z

remove_raw() in dm_btree_remove() may fail due to IO read error (e.g. read the content of origin block fails during shadowing), and the value of shadow_spine::root is uninitialized, but the uninitialized value is still assign to new_root in the end of dm_btree_remove(). For dm-thin, the value of pmd->details_root or pmd->root will become an uninitialized value, so if trying to read details_info tree again out-of-bound memory may occur as showed below: general protection fault, probably for non-canonical address 0x3fdcb14c8d7520 CPU: 4 PID: 515 Comm: dmsetup Not tainted 5.13.0-rc6 Hardware name: QEMU Standard PC RIP: 0010:metadata_ll_load_ie+0x14/0x30 Call Trace: sm_metadata_count_is_more_than_one+0xb9/0xe0 dm_tm_shadow_block+0x52/0x1c0 shadow_step+0x59/0xf0 remove_raw+0xb2/0x170 dm_btree_remove+0xf4/0x1c0 dm_pool_delete_thin_device+0xc3/0x140 pool_message+0x218/0x2b0 target_message+0x251/0x290 ctl_ioctl+0x1c4/0x4d0 dm_ctl_ioctl+0xe/0x20 __x64_sys_ioctl+0x7b/0xb0 do_syscall_64+0x40/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xae Fixing it by only assign new_root when removal succeeds Signed-off-by: Hou Tao Cc: stable@vger.kernel.org Signed-off-by: Mike Snitzer

dm space map disk: cache a small number of index entries

2021-06-04T16:07:23Z

The disk space map stores it's index entries in a btree, these are accessed very frequently, so having a few cached makes a big difference to performance. With this change provisioning a new block takes roughly 20% less cpu. Signed-off-by: Joe Thornber 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