- 07 Oct, 2020 40 commits
-
-
Anand Jain authored
The function is short and simple, we can get rid of the declaration as it's not necessary for a static function. Move it before its first caller. No functional changes. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Anand Jain authored
The function does not have a common exit block and returns immediatelly so there's no point having the goto. Remove the two cases. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Anand Jain authored
We can check the argument value directly, no need for the temporary variable. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Anand Jain authored
In the function btrfs_init_dev_replace_tgtdev(), the local variable devices is used only once, we can remove it. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Anand Jain authored
On a mounted sprout filesystem, all threads now are using the sprout::device_list_mutex, and this is the only code using the seed::device_list_mutex. This patch converts to use the sprouts fs_info->fs_devices->device_list_mutex. The same reasoning holds true here, that device delete is holding the sprout::device_list_mutex. Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Anand Jain authored
On an fs mounted using a sprout device, the seed fs_devices are maintained in a linked list under fs_info->fs_devices. Each seeds fs_devices also has device_list_mutex initialized to protect against the potential race with delete threads. But the delete thread (at btrfs_rm_device()) is holding the fs_info::fs_devices::device_list_mutex mutex which belongs to sprout device_list_mutex instead of seed device_list_mutex. Moreover, there aren't any significient benefits in using the seed::device_list_mutex instead of sprout::device_list_mutex. So this patch converts them of using the seed::device_list_mutex to sprout::device_list_mutex. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Anand Jain authored
btrfs_sysfs_add_fs_devices() is called by btrfs_sysfs_add_mounted(). btrfs_sysfs_add_mounted() assumes that btrfs_sysfs_add_fs_devices() will either add sysfs entries for all the devices or none. So this patch keeps up to its caller expecatation and cleans up the created sysfs entries if it has to fail at some device in the list. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Anand Jain authored
We don't initialize the sysfs devid kobject and device-link yet for the seed devices in an sprouted filesystem. So this patch initializes the seed device devid kobject and the device link in the sysfs. Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Anand Jain authored
Similar to btrfs_sysfs_add_devices_dir()'s refactoring, split btrfs_sysfs_remove_devices_dir() so that we don't have to use the device argument to indicate whether to free all devices or just one device. Export btrfs_sysfs_remove_device() as device operations outside of sysfs.c now calls this instead of btrfs_sysfs_remove_devices_dir(). btrfs_sysfs_remove_devices_dir() is renamed to btrfs_sysfs_remove_fs_devices() to suite its new role. Now, no one outside of sysfs.c calls btrfs_sysfs_remove_fs_devices() so it is redeclared s static. And the same function had to be moved before its first caller. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Anand Jain authored
When we add a device we need to add it to sysfs, so instead of using the btrfs_sysfs_add_devices_dir() fs_devices argument to specify whether to add a device or all of fs_devices, call the helper function directly btrfs_sysfs_add_device() and thus make it non-static. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Anand Jain authored
btrfs_sysfs_remove_devices_dir() return value is unused declare it as void. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Anand Jain authored
btrfs_sysfs_remove_devices_dir() removes device link and devid kobject (sysfs entries) for a device or all the devices in the btrfs_fs_devices. In preparation to remove these sysfs entries for the seed as well, add a btrfs_sysfs_remove_device() helper function and avoid code duplication. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Anand Jain authored
btrfs_sysfs_add_devices_dir() adds device link and devid kobject (sysfs entries) for a device or all the devices in the btrfs_fs_devices. In preparation to add these sysfs entries for the seed as well, add a btrfs_sysfs_add_device() helper function and avoid code duplication. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Anand Jain authored
If you replace a seed device in a sprouted fs, it appears to have successfully replaced the seed device, but if you look closely, it didn't. Here is an example. $ mkfs.btrfs /dev/sda $ btrfstune -S1 /dev/sda $ mount /dev/sda /btrfs $ btrfs device add /dev/sdb /btrfs $ umount /btrfs $ btrfs device scan --forget $ mount -o device=/dev/sda /dev/sdb /btrfs $ btrfs replace start -f /dev/sda /dev/sdc /btrfs $ echo $? 0 BTRFS info (device sdb): dev_replace from /dev/sda (devid 1) to /dev/sdc started BTRFS info (device sdb): dev_replace from /dev/sda (devid 1) to /dev/sdc finished $ btrfs fi show Label: none uuid: ab2c88b7-be81-4a7e-9849-c3666e7f9f4f Total devices 2 FS bytes used 256.00KiB devid 1 size 3.00GiB used 520.00MiB path /dev/sdc devid 2 size 3.00GiB used 896.00MiB path /dev/sdb Label: none uuid: 10bd3202-0415-43af-96a8-d5409f310a7e Total devices 1 FS bytes used 128.00KiB devid 1 size 3.00GiB used 536.00MiB path /dev/sda So as per the replace start command and kernel log replace was successful. Now let's try to clean mount. $ umount /btrfs $ btrfs device scan --forget $ mount -o device=/dev/sdc /dev/sdb /btrfs mount: /btrfs: wrong fs type, bad option, bad superblock on /dev/sdb, missing codepage or helper program, or other error. [ 636.157517] BTRFS error (device sdc): failed to read chunk tree: -2 [ 636.180177] BTRFS error (device sdc): open_ctree failed That's because per dev items it is still looking for the original seed device. $ btrfs inspect-internal dump-tree -d /dev/sdb item 0 key (DEV_ITEMS DEV_ITEM 1) itemoff 16185 itemsize 98 devid 1 total_bytes 3221225472 bytes_used 545259520 io_align 4096 io_width 4096 sector_size 4096 type 0 generation 6 start_offset 0 dev_group 0 seek_speed 0 bandwidth 0 uuid 59368f50-9af2-4b17-91da-8a783cc418d4 <--- seed uuid fsid 10bd3202-0415-43af-96a8-d5409f310a7e <--- seed fsid item 1 key (DEV_ITEMS DEV_ITEM 2) itemoff 16087 itemsize 98 devid 2 total_bytes 3221225472 bytes_used 939524096 io_align 4096 io_width 4096 sector_size 4096 type 0 generation 0 start_offset 0 dev_group 0 seek_speed 0 bandwidth 0 uuid 56a0a6bc-4630-4998-8daf-3c3030c4256a <- sprout uuid fsid ab2c88b7-be81-4a7e-9849-c3666e7f9f4f <- sprout fsid But the replaced target has the following uuid+fsid in its superblock which doesn't match with the expected uuid+fsid in its devitem. $ btrfs in dump-super /dev/sdc | egrep '^generation|dev_item.uuid|dev_item.fsid|devid' generation 20 dev_item.uuid 59368f50-9af2-4b17-91da-8a783cc418d4 dev_item.fsid ab2c88b7-be81-4a7e-9849-c3666e7f9f4f [match] dev_item.devid 1 So if you provide the original seed device the mount shall be successful. Which so long happening in the test case btrfs/163. $ btrfs device scan --forget $ mount -o device=/dev/sda /dev/sdb /btrfs Fix in this patch: If a seed is not sprouted then there is no replacement of it, because of its read-only filesystem with a read-only device. Similarly, in the case of a sprouted filesystem, the seed device is still read only. So, mark it as you can't replace a seed device, you can only add a new device and then delete the seed device. If replace is attempted then returns -EINVAL. Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Anand Jain authored
Systems booting without the initramfs seems to scan an unusual kind of device path (/dev/root). And at a later time, the device is updated to the correct path. We generally print the process name and PID of the process scanning the device but we don't capture the same information if the device path is rescanned with a different pathname. The current message is too long, so drop the unnecessary UUID and add process name and PID. While at this also update the duplicate device warning to include the process name and PID so the messages are consistent CC: stable@vger.kernel.org # 4.19+ Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=89721Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Josef Bacik authored
I'm a actual human being so am incapable of converting u64 to s64 in my head, so add a helper to get the pretty name of a root objectid and use that helper to spit out the name for any special roots for leaked roots, so I don't have to scratch my head and figure out which root I messed up the refs for. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Goldwyn Rodrigues authored
/sys/fs/<fsid>/exclusive_operation contains the currently executing exclusive operation. Add a sysfs_notify() when operation end, so userspace can be notified of exclusive operation is finished. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Goldwyn Rodrigues authored
Instead of using a flag bit for exclusive operation, use a variable to store which exclusive operation is being performed. Introduce an API to start and finish an exclusive operation. This would enable another way for tools to check which operation is running on why starting an exclusive operation failed. The followup patch adds a sysfs_notify() to alert userspace when the state changes, so userspace can perform select() on it to get notified of the change. This would enable us to enqueue a command which will wait for current exclusive operation to complete before issuing the next exclusive operation. This has been done synchronously as opposed to a background process, or else error collection (if any) will become difficult. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> [ update comments ] Signed-off-by: David Sterba <dsterba@suse.com>
-
Josef Bacik authored
While running btrfs/061, btrfs/073, btrfs/078, or btrfs/178 we hit the following lockdep splat: ====================================================== WARNING: possible circular locking dependency detected 5.9.0-rc3+ #4 Not tainted ------------------------------------------------------ kswapd0/100 is trying to acquire lock: ffff96ecc22ef4a0 (&delayed_node->mutex){+.+.}-{3:3}, at: __btrfs_release_delayed_node.part.0+0x3f/0x330 but task is already holding lock: ffffffff8dd74700 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x5/0x30 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (fs_reclaim){+.+.}-{0:0}: fs_reclaim_acquire+0x65/0x80 slab_pre_alloc_hook.constprop.0+0x20/0x200 kmem_cache_alloc+0x37/0x270 alloc_inode+0x82/0xb0 iget_locked+0x10d/0x2c0 kernfs_get_inode+0x1b/0x130 kernfs_get_tree+0x136/0x240 sysfs_get_tree+0x16/0x40 vfs_get_tree+0x28/0xc0 path_mount+0x434/0xc00 __x64_sys_mount+0xe3/0x120 do_syscall_64+0x33/0x40 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #2 (kernfs_mutex){+.+.}-{3:3}: __mutex_lock+0x7e/0x7e0 kernfs_add_one+0x23/0x150 kernfs_create_link+0x63/0xa0 sysfs_do_create_link_sd+0x5e/0xd0 btrfs_sysfs_add_devices_dir+0x81/0x130 btrfs_init_new_device+0x67f/0x1250 btrfs_ioctl+0x1ef/0x2e20 __x64_sys_ioctl+0x83/0xb0 do_syscall_64+0x33/0x40 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #1 (&fs_info->chunk_mutex){+.+.}-{3:3}: __mutex_lock+0x7e/0x7e0 btrfs_chunk_alloc+0x125/0x3a0 find_free_extent+0xdf6/0x1210 btrfs_reserve_extent+0xb3/0x1b0 btrfs_alloc_tree_block+0xb0/0x310 alloc_tree_block_no_bg_flush+0x4a/0x60 __btrfs_cow_block+0x11a/0x530 btrfs_cow_block+0x104/0x220 btrfs_search_slot+0x52e/0x9d0 btrfs_insert_empty_items+0x64/0xb0 btrfs_insert_delayed_items+0x90/0x4f0 btrfs_commit_inode_delayed_items+0x93/0x140 btrfs_log_inode+0x5de/0x2020 btrfs_log_inode_parent+0x429/0xc90 btrfs_log_new_name+0x95/0x9b btrfs_rename2+0xbb9/0x1800 vfs_rename+0x64f/0x9f0 do_renameat2+0x320/0x4e0 __x64_sys_rename+0x1f/0x30 do_syscall_64+0x33/0x40 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #0 (&delayed_node->mutex){+.+.}-{3:3}: __lock_acquire+0x119c/0x1fc0 lock_acquire+0xa7/0x3d0 __mutex_lock+0x7e/0x7e0 __btrfs_release_delayed_node.part.0+0x3f/0x330 btrfs_evict_inode+0x24c/0x500 evict+0xcf/0x1f0 dispose_list+0x48/0x70 prune_icache_sb+0x44/0x50 super_cache_scan+0x161/0x1e0 do_shrink_slab+0x178/0x3c0 shrink_slab+0x17c/0x290 shrink_node+0x2b2/0x6d0 balance_pgdat+0x30a/0x670 kswapd+0x213/0x4c0 kthread+0x138/0x160 ret_from_fork+0x1f/0x30 other info that might help us debug this: Chain exists of: &delayed_node->mutex --> kernfs_mutex --> fs_reclaim Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(fs_reclaim); lock(kernfs_mutex); lock(fs_reclaim); lock(&delayed_node->mutex); *** DEADLOCK *** 3 locks held by kswapd0/100: #0: ffffffff8dd74700 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x5/0x30 #1: ffffffff8dd65c50 (shrinker_rwsem){++++}-{3:3}, at: shrink_slab+0x115/0x290 #2: ffff96ed2ade30e0 (&type->s_umount_key#36){++++}-{3:3}, at: super_cache_scan+0x38/0x1e0 stack backtrace: CPU: 0 PID: 100 Comm: kswapd0 Not tainted 5.9.0-rc3+ #4 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014 Call Trace: dump_stack+0x8b/0xb8 check_noncircular+0x12d/0x150 __lock_acquire+0x119c/0x1fc0 lock_acquire+0xa7/0x3d0 ? __btrfs_release_delayed_node.part.0+0x3f/0x330 __mutex_lock+0x7e/0x7e0 ? __btrfs_release_delayed_node.part.0+0x3f/0x330 ? __btrfs_release_delayed_node.part.0+0x3f/0x330 ? lock_acquire+0xa7/0x3d0 ? find_held_lock+0x2b/0x80 __btrfs_release_delayed_node.part.0+0x3f/0x330 btrfs_evict_inode+0x24c/0x500 evict+0xcf/0x1f0 dispose_list+0x48/0x70 prune_icache_sb+0x44/0x50 super_cache_scan+0x161/0x1e0 do_shrink_slab+0x178/0x3c0 shrink_slab+0x17c/0x290 shrink_node+0x2b2/0x6d0 balance_pgdat+0x30a/0x670 kswapd+0x213/0x4c0 ? _raw_spin_unlock_irqrestore+0x41/0x50 ? add_wait_queue_exclusive+0x70/0x70 ? balance_pgdat+0x670/0x670 kthread+0x138/0x160 ? kthread_create_worker_on_cpu+0x40/0x40 ret_from_fork+0x1f/0x30 This happens because we are holding the chunk_mutex at the time of adding in a new device. However we only need to hold the device_list_mutex, as we're going to iterate over the fs_devices devices. Move the sysfs init stuff outside of the chunk_mutex to get rid of this lockdep splat. CC: stable@vger.kernel.org # 4.4.x: f3cd2c58: btrfs: sysfs, rename device_link add/remove functions CC: stable@vger.kernel.org # 4.4.x Reported-by: David Sterba <dsterba@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Nikolay Borisov authored
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Nikolay Borisov authored
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Nikolay Borisov authored
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Nikolay Borisov authored
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Nikolay Borisov authored
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Nikolay Borisov authored
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Nikolay Borisov authored
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Nikolay Borisov authored
It's counterintuitive to have a function named btrfs_inode_xxx which takes a generic inode. Also move the function to btrfs_inode.h so that it has access to the definition of struct btrfs_inode. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Nikolay Borisov authored
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Nikolay Borisov authored
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Nikolay Borisov authored
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Nikolay Borisov authored
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Josef Bacik authored
I've made this change separate since it requires both of the newly added NESTED flags and I didn't want to slip it into one of those changes. If we do a double split of a node we can end up doing a BTRFS_NESTED_SPLIT on level 0, which throws lockdep off because it appears as a double lock. Since we're maxed out on subclasses, use BTRFS_NESTED_NEW_ROOT if we had to do a double split. This is OK because we won't have to do a double split if we had to insert a new root, and the new root would be at a higher level anyway. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Josef Bacik authored
The way we add new roots is confusing from a locking perspective for lockdep. We generally have the rule that we lock things in order from highest level to lowest, but in the case of adding a new level to the tree we actually allocate a new block for the root, which makes the locking go in reverse. A similar issue exists for snapshotting, we cow the original root for the root of a new tree, however they're at the same level. Address this by using BTRFS_NESTING_NEW_ROOT for these operations. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Josef Bacik authored
If we are splitting a leaf/node, we could do something like the following lock(leaf) BTRFS_NESTING_NORMAL lock(left) BTRFS_NESTING_LEFT + BTRFS_NESTING_COW push from leaf -> left reset path to point to left split left allocate new block, lock block BTRFS_NESTING_SPLIT at the new block point we need to have a different nesting level, because we have already used either BTRFS_NESTING_LEFT or BTRFS_NESTING_RIGHT when pushing items from the original leaf into the adjacent leaves. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Josef Bacik authored
For similar reasons as BTRFS_NESTING_COW, we need BTRFS_NESTING_LEFT/RIGHT_COW. The pattern is this lock leaf -> BTRFS_NESTING_NORMAL cow leaf -> BTRFS_NESTING_COW split leaf lock left -> BTRFS_NESTING_LEFT cow left -> BTRFS_NESTING_LEFT_COW We need this in order to indicate to lockdep that these locks are discrete and are being taken in a safe order. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Josef Bacik authored
Our lockdep maps are based on rootid+level, however in some cases we will lock adjacent blocks on the same level, namely in searching forward or in split/balance. Because of this lockdep will complain, so we need a separate subclass to indicate to lockdep that these are different locks. lock leaf -> BTRFS_NESTING_NORMAL cow leaf -> BTRFS_NESTING_COW split leaf lock left -> BTRFS_NESTING_LEFT lock right -> BTRFS_NESTING_RIGHT The above graph illustrates the need for this new nesting subclass. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Josef Bacik authored
When we COW a block we are holding a lock on the original block, and then we lock the new COW block. Because our lockdep maps are based on root + level, this will make lockdep complain. We need a way to indicate a subclass for locking the COW'ed block, so plumb through our btrfs_lock_nesting from btrfs_cow_block down to the btrfs_init_buffer, and then introduce BTRFS_NESTING_COW to be used for cow'ing blocks. The reason I've added all this extra infrastructure is because there will be need of different nesting classes in follow up patches. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Josef Bacik authored
We will need these when we switch to an rwsem, so plumb in the infrastructure here to use later on. I violate the 80 character limit some here because it'll be cleaned up later. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Josef Bacik authored
Our current tree locking stuff allows us to recurse with read locks if we're already holding the write lock. This is necessary for the space cache inode, as we could be holding a lock on the root_tree root when we need to cache a block group, and thus need to be able to read down the root_tree to read in the inode cache. We can get away with this in our current locking, but we won't be able to with a rwsem. Handle this by purposefully annotating the places where we require recursion, so that in the future we can maybe come up with a way to avoid the recursion. In the case of the free space inode, this will be superseded by the free space tree. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-
Josef Bacik authored
Nested locking with lockdep and everything else refers to lock hierarchy within the same lock map. This is how we indicate the same locks for different objects are ok to take in a specific order, for our use case that would be to take the lock on a leaf and then take a lock on an adjacent leaf. What ->lock_nested _actually_ refers to is if we happen to already be holding the write lock on the extent buffer and we're allowing a read lock to be taken on that extent buffer, which is recursion. Rename this so we don't get confused when we switch to a rwsem and have to start using the _nested helpers. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
-