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![Nikolay Borisov](/assets/img/avatar_default.png)
With these fixes space-info.c is clear for W=1 warnings, namely the following ones are fixed: fs/btrfs/space-info.c:575: warning: Function parameter or member 'fs_info' not described in 'may_commit_transaction' fs/btrfs/space-info.c:575: warning: Function parameter or member 'space_info' not described in 'may_commit_transaction' fs/btrfs/space-info.c:1231: warning: Function parameter or member 'fs_info' not described in 'handle_reserve_ticket' fs/btrfs/space-info.c:1231: warning: Function parameter or member 'space_info' not described in 'handle_reserve_ticket' fs/btrfs/space-info.c:1231: warning: Function parameter or member 'ticket' not described in 'handle_reserve_ticket' fs/btrfs/space-info.c:1231: warning: Function parameter or member 'flush' not described in 'handle_reserve_ticket' fs/btrfs/space-info.c:1315: warning: Function parameter or member 'fs_info' not described in '__reserve_bytes' fs/btrfs/space-info.c:1315: warning: Function parameter or member 'space_info' not described in '__reserve_bytes' fs/btrfs/space-info.c:1315: warning: Function parameter or member 'orig_bytes' not described in '__reserve_bytes' fs/btrfs/space-info.c:1315: warning: Function parameter or member 'flush' not described in '__reserve_bytes' fs/btrfs/space-info.c:1427: warning: Function parameter or member 'root' not described in 'btrfs_reserve_metadata_bytes' fs/btrfs/space-info.c:1427: warning: Function parameter or member 'block_rsv' not described in 'btrfs_reserve_metadata_bytes' fs/btrfs/space-info.c:1427: warning: Function parameter or member 'orig_bytes' not described in 'btrfs_reserve_metadata_bytes' fs/btrfs/space-info.c:1427: warning: Function parameter or member 'flush' not described in 'btrfs_reserve_metadata_bytes' fs/btrfs/space-info.c:1462: warning: Function parameter or member 'fs_info' not described in 'btrfs_reserve_data_bytes' fs/btrfs/space-info.c:1462: warning: Function parameter or member 'bytes' not described in 'btrfs_reserve_data_bytes' fs/btrfs/space-info.c:1462: warning: Function parameter or member 'flush' not described in 'btrfs_reserve_data_bytes' Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
1482 lines
46 KiB
C
1482 lines
46 KiB
C
// SPDX-License-Identifier: GPL-2.0
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#include "misc.h"
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#include "ctree.h"
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#include "space-info.h"
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#include "sysfs.h"
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#include "volumes.h"
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#include "free-space-cache.h"
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#include "ordered-data.h"
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#include "transaction.h"
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#include "block-group.h"
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/*
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* HOW DOES SPACE RESERVATION WORK
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*
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* If you want to know about delalloc specifically, there is a separate comment
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* for that with the delalloc code. This comment is about how the whole system
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* works generally.
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*
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* BASIC CONCEPTS
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*
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* 1) space_info. This is the ultimate arbiter of how much space we can use.
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* There's a description of the bytes_ fields with the struct declaration,
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* refer to that for specifics on each field. Suffice it to say that for
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* reservations we care about total_bytes - SUM(space_info->bytes_) when
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* determining if there is space to make an allocation. There is a space_info
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* for METADATA, SYSTEM, and DATA areas.
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*
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* 2) block_rsv's. These are basically buckets for every different type of
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* metadata reservation we have. You can see the comment in the block_rsv
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* code on the rules for each type, but generally block_rsv->reserved is how
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* much space is accounted for in space_info->bytes_may_use.
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*
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* 3) btrfs_calc*_size. These are the worst case calculations we used based
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* on the number of items we will want to modify. We have one for changing
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* items, and one for inserting new items. Generally we use these helpers to
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* determine the size of the block reserves, and then use the actual bytes
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* values to adjust the space_info counters.
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*
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* MAKING RESERVATIONS, THE NORMAL CASE
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*
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* We call into either btrfs_reserve_data_bytes() or
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* btrfs_reserve_metadata_bytes(), depending on which we're looking for, with
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* num_bytes we want to reserve.
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*
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* ->reserve
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* space_info->bytes_may_reserve += num_bytes
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*
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* ->extent allocation
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* Call btrfs_add_reserved_bytes() which does
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* space_info->bytes_may_reserve -= num_bytes
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* space_info->bytes_reserved += extent_bytes
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*
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* ->insert reference
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* Call btrfs_update_block_group() which does
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* space_info->bytes_reserved -= extent_bytes
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* space_info->bytes_used += extent_bytes
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*
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* MAKING RESERVATIONS, FLUSHING NORMALLY (non-priority)
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*
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* Assume we are unable to simply make the reservation because we do not have
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* enough space
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*
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* -> __reserve_bytes
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* create a reserve_ticket with ->bytes set to our reservation, add it to
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* the tail of space_info->tickets, kick async flush thread
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*
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* ->handle_reserve_ticket
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* wait on ticket->wait for ->bytes to be reduced to 0, or ->error to be set
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* on the ticket.
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*
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* -> btrfs_async_reclaim_metadata_space/btrfs_async_reclaim_data_space
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* Flushes various things attempting to free up space.
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*
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* -> btrfs_try_granting_tickets()
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* This is called by anything that either subtracts space from
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* space_info->bytes_may_use, ->bytes_pinned, etc, or adds to the
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* space_info->total_bytes. This loops through the ->priority_tickets and
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* then the ->tickets list checking to see if the reservation can be
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* completed. If it can the space is added to space_info->bytes_may_use and
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* the ticket is woken up.
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*
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* -> ticket wakeup
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* Check if ->bytes == 0, if it does we got our reservation and we can carry
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* on, if not return the appropriate error (ENOSPC, but can be EINTR if we
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* were interrupted.)
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*
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* MAKING RESERVATIONS, FLUSHING HIGH PRIORITY
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*
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* Same as the above, except we add ourselves to the
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* space_info->priority_tickets, and we do not use ticket->wait, we simply
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* call flush_space() ourselves for the states that are safe for us to call
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* without deadlocking and hope for the best.
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*
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* THE FLUSHING STATES
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*
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* Generally speaking we will have two cases for each state, a "nice" state
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* and a "ALL THE THINGS" state. In btrfs we delay a lot of work in order to
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* reduce the locking over head on the various trees, and even to keep from
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* doing any work at all in the case of delayed refs. Each of these delayed
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* things however hold reservations, and so letting them run allows us to
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* reclaim space so we can make new reservations.
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*
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* FLUSH_DELAYED_ITEMS
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* Every inode has a delayed item to update the inode. Take a simple write
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* for example, we would update the inode item at write time to update the
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* mtime, and then again at finish_ordered_io() time in order to update the
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* isize or bytes. We keep these delayed items to coalesce these operations
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* into a single operation done on demand. These are an easy way to reclaim
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* metadata space.
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*
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* FLUSH_DELALLOC
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* Look at the delalloc comment to get an idea of how much space is reserved
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* for delayed allocation. We can reclaim some of this space simply by
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* running delalloc, but usually we need to wait for ordered extents to
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* reclaim the bulk of this space.
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*
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* FLUSH_DELAYED_REFS
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* We have a block reserve for the outstanding delayed refs space, and every
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* delayed ref operation holds a reservation. Running these is a quick way
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* to reclaim space, but we want to hold this until the end because COW can
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* churn a lot and we can avoid making some extent tree modifications if we
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* are able to delay for as long as possible.
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*
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* ALLOC_CHUNK
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* We will skip this the first time through space reservation, because of
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* overcommit and we don't want to have a lot of useless metadata space when
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* our worst case reservations will likely never come true.
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*
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* RUN_DELAYED_IPUTS
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* If we're freeing inodes we're likely freeing checksums, file extent
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* items, and extent tree items. Loads of space could be freed up by these
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* operations, however they won't be usable until the transaction commits.
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*
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* COMMIT_TRANS
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* may_commit_transaction() is the ultimate arbiter on whether we commit the
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* transaction or not. In order to avoid constantly churning we do all the
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* above flushing first and then commit the transaction as the last resort.
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* However we need to take into account things like pinned space that would
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* be freed, plus any delayed work we may not have gotten rid of in the case
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* of metadata.
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*
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* OVERCOMMIT
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*
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* Because we hold so many reservations for metadata we will allow you to
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* reserve more space than is currently free in the currently allocate
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* metadata space. This only happens with metadata, data does not allow
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* overcommitting.
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*
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* You can see the current logic for when we allow overcommit in
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* btrfs_can_overcommit(), but it only applies to unallocated space. If there
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* is no unallocated space to be had, all reservations are kept within the
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* free space in the allocated metadata chunks.
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*
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* Because of overcommitting, you generally want to use the
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* btrfs_can_overcommit() logic for metadata allocations, as it does the right
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* thing with or without extra unallocated space.
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*/
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u64 __pure btrfs_space_info_used(struct btrfs_space_info *s_info,
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bool may_use_included)
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{
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ASSERT(s_info);
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return s_info->bytes_used + s_info->bytes_reserved +
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s_info->bytes_pinned + s_info->bytes_readonly +
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(may_use_included ? s_info->bytes_may_use : 0);
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}
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/*
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* after adding space to the filesystem, we need to clear the full flags
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* on all the space infos.
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*/
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void btrfs_clear_space_info_full(struct btrfs_fs_info *info)
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{
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struct list_head *head = &info->space_info;
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struct btrfs_space_info *found;
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list_for_each_entry(found, head, list)
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found->full = 0;
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}
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static int create_space_info(struct btrfs_fs_info *info, u64 flags)
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{
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struct btrfs_space_info *space_info;
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int i;
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int ret;
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space_info = kzalloc(sizeof(*space_info), GFP_NOFS);
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if (!space_info)
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return -ENOMEM;
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ret = percpu_counter_init(&space_info->total_bytes_pinned, 0,
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GFP_KERNEL);
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if (ret) {
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kfree(space_info);
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return ret;
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}
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for (i = 0; i < BTRFS_NR_RAID_TYPES; i++)
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INIT_LIST_HEAD(&space_info->block_groups[i]);
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init_rwsem(&space_info->groups_sem);
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spin_lock_init(&space_info->lock);
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space_info->flags = flags & BTRFS_BLOCK_GROUP_TYPE_MASK;
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space_info->force_alloc = CHUNK_ALLOC_NO_FORCE;
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INIT_LIST_HEAD(&space_info->ro_bgs);
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INIT_LIST_HEAD(&space_info->tickets);
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INIT_LIST_HEAD(&space_info->priority_tickets);
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ret = btrfs_sysfs_add_space_info_type(info, space_info);
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if (ret)
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return ret;
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list_add(&space_info->list, &info->space_info);
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if (flags & BTRFS_BLOCK_GROUP_DATA)
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info->data_sinfo = space_info;
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return ret;
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}
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int btrfs_init_space_info(struct btrfs_fs_info *fs_info)
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{
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struct btrfs_super_block *disk_super;
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u64 features;
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u64 flags;
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int mixed = 0;
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int ret;
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disk_super = fs_info->super_copy;
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if (!btrfs_super_root(disk_super))
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return -EINVAL;
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features = btrfs_super_incompat_flags(disk_super);
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if (features & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
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mixed = 1;
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flags = BTRFS_BLOCK_GROUP_SYSTEM;
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ret = create_space_info(fs_info, flags);
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if (ret)
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goto out;
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if (mixed) {
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flags = BTRFS_BLOCK_GROUP_METADATA | BTRFS_BLOCK_GROUP_DATA;
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ret = create_space_info(fs_info, flags);
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} else {
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flags = BTRFS_BLOCK_GROUP_METADATA;
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ret = create_space_info(fs_info, flags);
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if (ret)
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goto out;
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flags = BTRFS_BLOCK_GROUP_DATA;
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ret = create_space_info(fs_info, flags);
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}
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out:
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return ret;
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}
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void btrfs_update_space_info(struct btrfs_fs_info *info, u64 flags,
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u64 total_bytes, u64 bytes_used,
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u64 bytes_readonly,
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struct btrfs_space_info **space_info)
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{
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struct btrfs_space_info *found;
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int factor;
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factor = btrfs_bg_type_to_factor(flags);
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found = btrfs_find_space_info(info, flags);
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ASSERT(found);
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spin_lock(&found->lock);
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found->total_bytes += total_bytes;
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found->disk_total += total_bytes * factor;
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found->bytes_used += bytes_used;
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found->disk_used += bytes_used * factor;
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found->bytes_readonly += bytes_readonly;
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if (total_bytes > 0)
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found->full = 0;
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btrfs_try_granting_tickets(info, found);
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spin_unlock(&found->lock);
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*space_info = found;
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}
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struct btrfs_space_info *btrfs_find_space_info(struct btrfs_fs_info *info,
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u64 flags)
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{
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struct list_head *head = &info->space_info;
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struct btrfs_space_info *found;
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flags &= BTRFS_BLOCK_GROUP_TYPE_MASK;
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list_for_each_entry(found, head, list) {
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if (found->flags & flags)
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return found;
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}
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return NULL;
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}
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static u64 calc_available_free_space(struct btrfs_fs_info *fs_info,
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struct btrfs_space_info *space_info,
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enum btrfs_reserve_flush_enum flush)
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{
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u64 profile;
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u64 avail;
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int factor;
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if (space_info->flags & BTRFS_BLOCK_GROUP_SYSTEM)
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profile = btrfs_system_alloc_profile(fs_info);
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else
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profile = btrfs_metadata_alloc_profile(fs_info);
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avail = atomic64_read(&fs_info->free_chunk_space);
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/*
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* If we have dup, raid1 or raid10 then only half of the free
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* space is actually usable. For raid56, the space info used
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* doesn't include the parity drive, so we don't have to
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* change the math
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*/
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factor = btrfs_bg_type_to_factor(profile);
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avail = div_u64(avail, factor);
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/*
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* If we aren't flushing all things, let us overcommit up to
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* 1/2th of the space. If we can flush, don't let us overcommit
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* too much, let it overcommit up to 1/8 of the space.
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*/
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if (flush == BTRFS_RESERVE_FLUSH_ALL)
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avail >>= 3;
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else
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avail >>= 1;
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return avail;
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}
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int btrfs_can_overcommit(struct btrfs_fs_info *fs_info,
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struct btrfs_space_info *space_info, u64 bytes,
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enum btrfs_reserve_flush_enum flush)
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{
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u64 avail;
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u64 used;
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/* Don't overcommit when in mixed mode */
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if (space_info->flags & BTRFS_BLOCK_GROUP_DATA)
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return 0;
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used = btrfs_space_info_used(space_info, true);
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avail = calc_available_free_space(fs_info, space_info, flush);
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if (used + bytes < space_info->total_bytes + avail)
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return 1;
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return 0;
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}
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static void remove_ticket(struct btrfs_space_info *space_info,
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struct reserve_ticket *ticket)
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{
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if (!list_empty(&ticket->list)) {
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list_del_init(&ticket->list);
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ASSERT(space_info->reclaim_size >= ticket->bytes);
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space_info->reclaim_size -= ticket->bytes;
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}
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}
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/*
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* This is for space we already have accounted in space_info->bytes_may_use, so
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* basically when we're returning space from block_rsv's.
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*/
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void btrfs_try_granting_tickets(struct btrfs_fs_info *fs_info,
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struct btrfs_space_info *space_info)
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{
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struct list_head *head;
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enum btrfs_reserve_flush_enum flush = BTRFS_RESERVE_NO_FLUSH;
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lockdep_assert_held(&space_info->lock);
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head = &space_info->priority_tickets;
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again:
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while (!list_empty(head)) {
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struct reserve_ticket *ticket;
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u64 used = btrfs_space_info_used(space_info, true);
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ticket = list_first_entry(head, struct reserve_ticket, list);
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/* Check and see if our ticket can be satisified now. */
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if ((used + ticket->bytes <= space_info->total_bytes) ||
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btrfs_can_overcommit(fs_info, space_info, ticket->bytes,
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flush)) {
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btrfs_space_info_update_bytes_may_use(fs_info,
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space_info,
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ticket->bytes);
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remove_ticket(space_info, ticket);
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ticket->bytes = 0;
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space_info->tickets_id++;
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wake_up(&ticket->wait);
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} else {
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break;
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}
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}
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if (head == &space_info->priority_tickets) {
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head = &space_info->tickets;
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flush = BTRFS_RESERVE_FLUSH_ALL;
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goto again;
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}
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}
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#define DUMP_BLOCK_RSV(fs_info, rsv_name) \
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do { \
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struct btrfs_block_rsv *__rsv = &(fs_info)->rsv_name; \
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spin_lock(&__rsv->lock); \
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btrfs_info(fs_info, #rsv_name ": size %llu reserved %llu", \
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__rsv->size, __rsv->reserved); \
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spin_unlock(&__rsv->lock); \
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} while (0)
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|
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static void __btrfs_dump_space_info(struct btrfs_fs_info *fs_info,
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struct btrfs_space_info *info)
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{
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lockdep_assert_held(&info->lock);
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btrfs_info(fs_info, "space_info %llu has %llu free, is %sfull",
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info->flags,
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info->total_bytes - btrfs_space_info_used(info, true),
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info->full ? "" : "not ");
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btrfs_info(fs_info,
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"space_info total=%llu, used=%llu, pinned=%llu, reserved=%llu, may_use=%llu, readonly=%llu",
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info->total_bytes, info->bytes_used, info->bytes_pinned,
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info->bytes_reserved, info->bytes_may_use,
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info->bytes_readonly);
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|
|
DUMP_BLOCK_RSV(fs_info, global_block_rsv);
|
|
DUMP_BLOCK_RSV(fs_info, trans_block_rsv);
|
|
DUMP_BLOCK_RSV(fs_info, chunk_block_rsv);
|
|
DUMP_BLOCK_RSV(fs_info, delayed_block_rsv);
|
|
DUMP_BLOCK_RSV(fs_info, delayed_refs_rsv);
|
|
|
|
}
|
|
|
|
void btrfs_dump_space_info(struct btrfs_fs_info *fs_info,
|
|
struct btrfs_space_info *info, u64 bytes,
|
|
int dump_block_groups)
|
|
{
|
|
struct btrfs_block_group *cache;
|
|
int index = 0;
|
|
|
|
spin_lock(&info->lock);
|
|
__btrfs_dump_space_info(fs_info, info);
|
|
spin_unlock(&info->lock);
|
|
|
|
if (!dump_block_groups)
|
|
return;
|
|
|
|
down_read(&info->groups_sem);
|
|
again:
|
|
list_for_each_entry(cache, &info->block_groups[index], list) {
|
|
spin_lock(&cache->lock);
|
|
btrfs_info(fs_info,
|
|
"block group %llu has %llu bytes, %llu used %llu pinned %llu reserved %s",
|
|
cache->start, cache->length, cache->used, cache->pinned,
|
|
cache->reserved, cache->ro ? "[readonly]" : "");
|
|
spin_unlock(&cache->lock);
|
|
btrfs_dump_free_space(cache, bytes);
|
|
}
|
|
if (++index < BTRFS_NR_RAID_TYPES)
|
|
goto again;
|
|
up_read(&info->groups_sem);
|
|
}
|
|
|
|
static inline u64 calc_reclaim_items_nr(struct btrfs_fs_info *fs_info,
|
|
u64 to_reclaim)
|
|
{
|
|
u64 bytes;
|
|
u64 nr;
|
|
|
|
bytes = btrfs_calc_insert_metadata_size(fs_info, 1);
|
|
nr = div64_u64(to_reclaim, bytes);
|
|
if (!nr)
|
|
nr = 1;
|
|
return nr;
|
|
}
|
|
|
|
#define EXTENT_SIZE_PER_ITEM SZ_256K
|
|
|
|
/*
|
|
* shrink metadata reservation for delalloc
|
|
*/
|
|
static void shrink_delalloc(struct btrfs_fs_info *fs_info,
|
|
struct btrfs_space_info *space_info,
|
|
u64 to_reclaim, bool wait_ordered)
|
|
{
|
|
struct btrfs_trans_handle *trans;
|
|
u64 delalloc_bytes;
|
|
u64 dio_bytes;
|
|
u64 items;
|
|
long time_left;
|
|
int loops;
|
|
|
|
/* Calc the number of the pages we need flush for space reservation */
|
|
if (to_reclaim == U64_MAX) {
|
|
items = U64_MAX;
|
|
} else {
|
|
/*
|
|
* to_reclaim is set to however much metadata we need to
|
|
* reclaim, but reclaiming that much data doesn't really track
|
|
* exactly, so increase the amount to reclaim by 2x in order to
|
|
* make sure we're flushing enough delalloc to hopefully reclaim
|
|
* some metadata reservations.
|
|
*/
|
|
items = calc_reclaim_items_nr(fs_info, to_reclaim) * 2;
|
|
to_reclaim = items * EXTENT_SIZE_PER_ITEM;
|
|
}
|
|
|
|
trans = (struct btrfs_trans_handle *)current->journal_info;
|
|
|
|
delalloc_bytes = percpu_counter_sum_positive(
|
|
&fs_info->delalloc_bytes);
|
|
dio_bytes = percpu_counter_sum_positive(&fs_info->dio_bytes);
|
|
if (delalloc_bytes == 0 && dio_bytes == 0) {
|
|
if (trans)
|
|
return;
|
|
if (wait_ordered)
|
|
btrfs_wait_ordered_roots(fs_info, items, 0, (u64)-1);
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* If we are doing more ordered than delalloc we need to just wait on
|
|
* ordered extents, otherwise we'll waste time trying to flush delalloc
|
|
* that likely won't give us the space back we need.
|
|
*/
|
|
if (dio_bytes > delalloc_bytes)
|
|
wait_ordered = true;
|
|
|
|
loops = 0;
|
|
while ((delalloc_bytes || dio_bytes) && loops < 3) {
|
|
u64 temp = min(delalloc_bytes, to_reclaim) >> PAGE_SHIFT;
|
|
long nr_pages = min_t(u64, temp, LONG_MAX);
|
|
|
|
btrfs_start_delalloc_roots(fs_info, nr_pages, true);
|
|
|
|
loops++;
|
|
if (wait_ordered && !trans) {
|
|
btrfs_wait_ordered_roots(fs_info, items, 0, (u64)-1);
|
|
} else {
|
|
time_left = schedule_timeout_killable(1);
|
|
if (time_left)
|
|
break;
|
|
}
|
|
|
|
spin_lock(&space_info->lock);
|
|
if (list_empty(&space_info->tickets) &&
|
|
list_empty(&space_info->priority_tickets)) {
|
|
spin_unlock(&space_info->lock);
|
|
break;
|
|
}
|
|
spin_unlock(&space_info->lock);
|
|
|
|
delalloc_bytes = percpu_counter_sum_positive(
|
|
&fs_info->delalloc_bytes);
|
|
dio_bytes = percpu_counter_sum_positive(&fs_info->dio_bytes);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Possibly commit the transaction if its ok to
|
|
*
|
|
* @fs_info: the filesystem
|
|
* @space_info: space_info we are checking for commit, either data or metadata
|
|
*
|
|
* This will check to make sure that committing the transaction will actually
|
|
* get us somewhere and then commit the transaction if it does. Otherwise it
|
|
* will return -ENOSPC.
|
|
*/
|
|
static int may_commit_transaction(struct btrfs_fs_info *fs_info,
|
|
struct btrfs_space_info *space_info)
|
|
{
|
|
struct reserve_ticket *ticket = NULL;
|
|
struct btrfs_block_rsv *delayed_rsv = &fs_info->delayed_block_rsv;
|
|
struct btrfs_block_rsv *delayed_refs_rsv = &fs_info->delayed_refs_rsv;
|
|
struct btrfs_block_rsv *trans_rsv = &fs_info->trans_block_rsv;
|
|
struct btrfs_trans_handle *trans;
|
|
u64 reclaim_bytes = 0;
|
|
u64 bytes_needed = 0;
|
|
u64 cur_free_bytes = 0;
|
|
|
|
trans = (struct btrfs_trans_handle *)current->journal_info;
|
|
if (trans)
|
|
return -EAGAIN;
|
|
|
|
spin_lock(&space_info->lock);
|
|
cur_free_bytes = btrfs_space_info_used(space_info, true);
|
|
if (cur_free_bytes < space_info->total_bytes)
|
|
cur_free_bytes = space_info->total_bytes - cur_free_bytes;
|
|
else
|
|
cur_free_bytes = 0;
|
|
|
|
if (!list_empty(&space_info->priority_tickets))
|
|
ticket = list_first_entry(&space_info->priority_tickets,
|
|
struct reserve_ticket, list);
|
|
else if (!list_empty(&space_info->tickets))
|
|
ticket = list_first_entry(&space_info->tickets,
|
|
struct reserve_ticket, list);
|
|
if (ticket)
|
|
bytes_needed = ticket->bytes;
|
|
|
|
if (bytes_needed > cur_free_bytes)
|
|
bytes_needed -= cur_free_bytes;
|
|
else
|
|
bytes_needed = 0;
|
|
spin_unlock(&space_info->lock);
|
|
|
|
if (!bytes_needed)
|
|
return 0;
|
|
|
|
trans = btrfs_join_transaction(fs_info->extent_root);
|
|
if (IS_ERR(trans))
|
|
return PTR_ERR(trans);
|
|
|
|
/*
|
|
* See if there is enough pinned space to make this reservation, or if
|
|
* we have block groups that are going to be freed, allowing us to
|
|
* possibly do a chunk allocation the next loop through.
|
|
*/
|
|
if (test_bit(BTRFS_TRANS_HAVE_FREE_BGS, &trans->transaction->flags) ||
|
|
__percpu_counter_compare(&space_info->total_bytes_pinned,
|
|
bytes_needed,
|
|
BTRFS_TOTAL_BYTES_PINNED_BATCH) >= 0)
|
|
goto commit;
|
|
|
|
/*
|
|
* See if there is some space in the delayed insertion reserve for this
|
|
* reservation. If the space_info's don't match (like for DATA or
|
|
* SYSTEM) then just go enospc, reclaiming this space won't recover any
|
|
* space to satisfy those reservations.
|
|
*/
|
|
if (space_info != delayed_rsv->space_info)
|
|
goto enospc;
|
|
|
|
spin_lock(&delayed_rsv->lock);
|
|
reclaim_bytes += delayed_rsv->reserved;
|
|
spin_unlock(&delayed_rsv->lock);
|
|
|
|
spin_lock(&delayed_refs_rsv->lock);
|
|
reclaim_bytes += delayed_refs_rsv->reserved;
|
|
spin_unlock(&delayed_refs_rsv->lock);
|
|
|
|
spin_lock(&trans_rsv->lock);
|
|
reclaim_bytes += trans_rsv->reserved;
|
|
spin_unlock(&trans_rsv->lock);
|
|
|
|
if (reclaim_bytes >= bytes_needed)
|
|
goto commit;
|
|
bytes_needed -= reclaim_bytes;
|
|
|
|
if (__percpu_counter_compare(&space_info->total_bytes_pinned,
|
|
bytes_needed,
|
|
BTRFS_TOTAL_BYTES_PINNED_BATCH) < 0)
|
|
goto enospc;
|
|
|
|
commit:
|
|
return btrfs_commit_transaction(trans);
|
|
enospc:
|
|
btrfs_end_transaction(trans);
|
|
return -ENOSPC;
|
|
}
|
|
|
|
/*
|
|
* Try to flush some data based on policy set by @state. This is only advisory
|
|
* and may fail for various reasons. The caller is supposed to examine the
|
|
* state of @space_info to detect the outcome.
|
|
*/
|
|
static void flush_space(struct btrfs_fs_info *fs_info,
|
|
struct btrfs_space_info *space_info, u64 num_bytes,
|
|
int state)
|
|
{
|
|
struct btrfs_root *root = fs_info->extent_root;
|
|
struct btrfs_trans_handle *trans;
|
|
int nr;
|
|
int ret = 0;
|
|
|
|
switch (state) {
|
|
case FLUSH_DELAYED_ITEMS_NR:
|
|
case FLUSH_DELAYED_ITEMS:
|
|
if (state == FLUSH_DELAYED_ITEMS_NR)
|
|
nr = calc_reclaim_items_nr(fs_info, num_bytes) * 2;
|
|
else
|
|
nr = -1;
|
|
|
|
trans = btrfs_join_transaction(root);
|
|
if (IS_ERR(trans)) {
|
|
ret = PTR_ERR(trans);
|
|
break;
|
|
}
|
|
ret = btrfs_run_delayed_items_nr(trans, nr);
|
|
btrfs_end_transaction(trans);
|
|
break;
|
|
case FLUSH_DELALLOC:
|
|
case FLUSH_DELALLOC_WAIT:
|
|
shrink_delalloc(fs_info, space_info, num_bytes,
|
|
state == FLUSH_DELALLOC_WAIT);
|
|
break;
|
|
case FLUSH_DELAYED_REFS_NR:
|
|
case FLUSH_DELAYED_REFS:
|
|
trans = btrfs_join_transaction(root);
|
|
if (IS_ERR(trans)) {
|
|
ret = PTR_ERR(trans);
|
|
break;
|
|
}
|
|
if (state == FLUSH_DELAYED_REFS_NR)
|
|
nr = calc_reclaim_items_nr(fs_info, num_bytes);
|
|
else
|
|
nr = 0;
|
|
btrfs_run_delayed_refs(trans, nr);
|
|
btrfs_end_transaction(trans);
|
|
break;
|
|
case ALLOC_CHUNK:
|
|
case ALLOC_CHUNK_FORCE:
|
|
trans = btrfs_join_transaction(root);
|
|
if (IS_ERR(trans)) {
|
|
ret = PTR_ERR(trans);
|
|
break;
|
|
}
|
|
ret = btrfs_chunk_alloc(trans,
|
|
btrfs_get_alloc_profile(fs_info, space_info->flags),
|
|
(state == ALLOC_CHUNK) ? CHUNK_ALLOC_NO_FORCE :
|
|
CHUNK_ALLOC_FORCE);
|
|
btrfs_end_transaction(trans);
|
|
if (ret > 0 || ret == -ENOSPC)
|
|
ret = 0;
|
|
break;
|
|
case RUN_DELAYED_IPUTS:
|
|
/*
|
|
* If we have pending delayed iputs then we could free up a
|
|
* bunch of pinned space, so make sure we run the iputs before
|
|
* we do our pinned bytes check below.
|
|
*/
|
|
btrfs_run_delayed_iputs(fs_info);
|
|
btrfs_wait_on_delayed_iputs(fs_info);
|
|
break;
|
|
case COMMIT_TRANS:
|
|
ret = may_commit_transaction(fs_info, space_info);
|
|
break;
|
|
default:
|
|
ret = -ENOSPC;
|
|
break;
|
|
}
|
|
|
|
trace_btrfs_flush_space(fs_info, space_info->flags, num_bytes, state,
|
|
ret);
|
|
return;
|
|
}
|
|
|
|
static inline u64
|
|
btrfs_calc_reclaim_metadata_size(struct btrfs_fs_info *fs_info,
|
|
struct btrfs_space_info *space_info)
|
|
{
|
|
u64 used;
|
|
u64 avail;
|
|
u64 expected;
|
|
u64 to_reclaim = space_info->reclaim_size;
|
|
|
|
lockdep_assert_held(&space_info->lock);
|
|
|
|
avail = calc_available_free_space(fs_info, space_info,
|
|
BTRFS_RESERVE_FLUSH_ALL);
|
|
used = btrfs_space_info_used(space_info, true);
|
|
|
|
/*
|
|
* We may be flushing because suddenly we have less space than we had
|
|
* before, and now we're well over-committed based on our current free
|
|
* space. If that's the case add in our overage so we make sure to put
|
|
* appropriate pressure on the flushing state machine.
|
|
*/
|
|
if (space_info->total_bytes + avail < used)
|
|
to_reclaim += used - (space_info->total_bytes + avail);
|
|
|
|
if (to_reclaim)
|
|
return to_reclaim;
|
|
|
|
to_reclaim = min_t(u64, num_online_cpus() * SZ_1M, SZ_16M);
|
|
if (btrfs_can_overcommit(fs_info, space_info, to_reclaim,
|
|
BTRFS_RESERVE_FLUSH_ALL))
|
|
return 0;
|
|
|
|
used = btrfs_space_info_used(space_info, true);
|
|
|
|
if (btrfs_can_overcommit(fs_info, space_info, SZ_1M,
|
|
BTRFS_RESERVE_FLUSH_ALL))
|
|
expected = div_factor_fine(space_info->total_bytes, 95);
|
|
else
|
|
expected = div_factor_fine(space_info->total_bytes, 90);
|
|
|
|
if (used > expected)
|
|
to_reclaim = used - expected;
|
|
else
|
|
to_reclaim = 0;
|
|
to_reclaim = min(to_reclaim, space_info->bytes_may_use +
|
|
space_info->bytes_reserved);
|
|
return to_reclaim;
|
|
}
|
|
|
|
static inline int need_do_async_reclaim(struct btrfs_fs_info *fs_info,
|
|
struct btrfs_space_info *space_info,
|
|
u64 used)
|
|
{
|
|
u64 thresh = div_factor_fine(space_info->total_bytes, 98);
|
|
|
|
/* If we're just plain full then async reclaim just slows us down. */
|
|
if ((space_info->bytes_used + space_info->bytes_reserved) >= thresh)
|
|
return 0;
|
|
|
|
if (!btrfs_calc_reclaim_metadata_size(fs_info, space_info))
|
|
return 0;
|
|
|
|
return (used >= thresh && !btrfs_fs_closing(fs_info) &&
|
|
!test_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state));
|
|
}
|
|
|
|
static bool steal_from_global_rsv(struct btrfs_fs_info *fs_info,
|
|
struct btrfs_space_info *space_info,
|
|
struct reserve_ticket *ticket)
|
|
{
|
|
struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
|
|
u64 min_bytes;
|
|
|
|
if (global_rsv->space_info != space_info)
|
|
return false;
|
|
|
|
spin_lock(&global_rsv->lock);
|
|
min_bytes = div_factor(global_rsv->size, 1);
|
|
if (global_rsv->reserved < min_bytes + ticket->bytes) {
|
|
spin_unlock(&global_rsv->lock);
|
|
return false;
|
|
}
|
|
global_rsv->reserved -= ticket->bytes;
|
|
remove_ticket(space_info, ticket);
|
|
ticket->bytes = 0;
|
|
wake_up(&ticket->wait);
|
|
space_info->tickets_id++;
|
|
if (global_rsv->reserved < global_rsv->size)
|
|
global_rsv->full = 0;
|
|
spin_unlock(&global_rsv->lock);
|
|
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* maybe_fail_all_tickets - we've exhausted our flushing, start failing tickets
|
|
* @fs_info - fs_info for this fs
|
|
* @space_info - the space info we were flushing
|
|
*
|
|
* We call this when we've exhausted our flushing ability and haven't made
|
|
* progress in satisfying tickets. The reservation code handles tickets in
|
|
* order, so if there is a large ticket first and then smaller ones we could
|
|
* very well satisfy the smaller tickets. This will attempt to wake up any
|
|
* tickets in the list to catch this case.
|
|
*
|
|
* This function returns true if it was able to make progress by clearing out
|
|
* other tickets, or if it stumbles across a ticket that was smaller than the
|
|
* first ticket.
|
|
*/
|
|
static bool maybe_fail_all_tickets(struct btrfs_fs_info *fs_info,
|
|
struct btrfs_space_info *space_info)
|
|
{
|
|
struct reserve_ticket *ticket;
|
|
u64 tickets_id = space_info->tickets_id;
|
|
u64 first_ticket_bytes = 0;
|
|
|
|
if (btrfs_test_opt(fs_info, ENOSPC_DEBUG)) {
|
|
btrfs_info(fs_info, "cannot satisfy tickets, dumping space info");
|
|
__btrfs_dump_space_info(fs_info, space_info);
|
|
}
|
|
|
|
while (!list_empty(&space_info->tickets) &&
|
|
tickets_id == space_info->tickets_id) {
|
|
ticket = list_first_entry(&space_info->tickets,
|
|
struct reserve_ticket, list);
|
|
|
|
if (ticket->steal &&
|
|
steal_from_global_rsv(fs_info, space_info, ticket))
|
|
return true;
|
|
|
|
/*
|
|
* may_commit_transaction will avoid committing the transaction
|
|
* if it doesn't feel like the space reclaimed by the commit
|
|
* would result in the ticket succeeding. However if we have a
|
|
* smaller ticket in the queue it may be small enough to be
|
|
* satisified by committing the transaction, so if any
|
|
* subsequent ticket is smaller than the first ticket go ahead
|
|
* and send us back for another loop through the enospc flushing
|
|
* code.
|
|
*/
|
|
if (first_ticket_bytes == 0)
|
|
first_ticket_bytes = ticket->bytes;
|
|
else if (first_ticket_bytes > ticket->bytes)
|
|
return true;
|
|
|
|
if (btrfs_test_opt(fs_info, ENOSPC_DEBUG))
|
|
btrfs_info(fs_info, "failing ticket with %llu bytes",
|
|
ticket->bytes);
|
|
|
|
remove_ticket(space_info, ticket);
|
|
ticket->error = -ENOSPC;
|
|
wake_up(&ticket->wait);
|
|
|
|
/*
|
|
* We're just throwing tickets away, so more flushing may not
|
|
* trip over btrfs_try_granting_tickets, so we need to call it
|
|
* here to see if we can make progress with the next ticket in
|
|
* the list.
|
|
*/
|
|
btrfs_try_granting_tickets(fs_info, space_info);
|
|
}
|
|
return (tickets_id != space_info->tickets_id);
|
|
}
|
|
|
|
/*
|
|
* This is for normal flushers, we can wait all goddamned day if we want to. We
|
|
* will loop and continuously try to flush as long as we are making progress.
|
|
* We count progress as clearing off tickets each time we have to loop.
|
|
*/
|
|
static void btrfs_async_reclaim_metadata_space(struct work_struct *work)
|
|
{
|
|
struct btrfs_fs_info *fs_info;
|
|
struct btrfs_space_info *space_info;
|
|
u64 to_reclaim;
|
|
int flush_state;
|
|
int commit_cycles = 0;
|
|
u64 last_tickets_id;
|
|
|
|
fs_info = container_of(work, struct btrfs_fs_info, async_reclaim_work);
|
|
space_info = btrfs_find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
|
|
|
|
spin_lock(&space_info->lock);
|
|
to_reclaim = btrfs_calc_reclaim_metadata_size(fs_info, space_info);
|
|
if (!to_reclaim) {
|
|
space_info->flush = 0;
|
|
spin_unlock(&space_info->lock);
|
|
return;
|
|
}
|
|
last_tickets_id = space_info->tickets_id;
|
|
spin_unlock(&space_info->lock);
|
|
|
|
flush_state = FLUSH_DELAYED_ITEMS_NR;
|
|
do {
|
|
flush_space(fs_info, space_info, to_reclaim, flush_state);
|
|
spin_lock(&space_info->lock);
|
|
if (list_empty(&space_info->tickets)) {
|
|
space_info->flush = 0;
|
|
spin_unlock(&space_info->lock);
|
|
return;
|
|
}
|
|
to_reclaim = btrfs_calc_reclaim_metadata_size(fs_info,
|
|
space_info);
|
|
if (last_tickets_id == space_info->tickets_id) {
|
|
flush_state++;
|
|
} else {
|
|
last_tickets_id = space_info->tickets_id;
|
|
flush_state = FLUSH_DELAYED_ITEMS_NR;
|
|
if (commit_cycles)
|
|
commit_cycles--;
|
|
}
|
|
|
|
/*
|
|
* We don't want to force a chunk allocation until we've tried
|
|
* pretty hard to reclaim space. Think of the case where we
|
|
* freed up a bunch of space and so have a lot of pinned space
|
|
* to reclaim. We would rather use that than possibly create a
|
|
* underutilized metadata chunk. So if this is our first run
|
|
* through the flushing state machine skip ALLOC_CHUNK_FORCE and
|
|
* commit the transaction. If nothing has changed the next go
|
|
* around then we can force a chunk allocation.
|
|
*/
|
|
if (flush_state == ALLOC_CHUNK_FORCE && !commit_cycles)
|
|
flush_state++;
|
|
|
|
if (flush_state > COMMIT_TRANS) {
|
|
commit_cycles++;
|
|
if (commit_cycles > 2) {
|
|
if (maybe_fail_all_tickets(fs_info, space_info)) {
|
|
flush_state = FLUSH_DELAYED_ITEMS_NR;
|
|
commit_cycles--;
|
|
} else {
|
|
space_info->flush = 0;
|
|
}
|
|
} else {
|
|
flush_state = FLUSH_DELAYED_ITEMS_NR;
|
|
}
|
|
}
|
|
spin_unlock(&space_info->lock);
|
|
} while (flush_state <= COMMIT_TRANS);
|
|
}
|
|
|
|
/*
|
|
* FLUSH_DELALLOC_WAIT:
|
|
* Space is freed from flushing delalloc in one of two ways.
|
|
*
|
|
* 1) compression is on and we allocate less space than we reserved
|
|
* 2) we are overwriting existing space
|
|
*
|
|
* For #1 that extra space is reclaimed as soon as the delalloc pages are
|
|
* COWed, by way of btrfs_add_reserved_bytes() which adds the actual extent
|
|
* length to ->bytes_reserved, and subtracts the reserved space from
|
|
* ->bytes_may_use.
|
|
*
|
|
* For #2 this is trickier. Once the ordered extent runs we will drop the
|
|
* extent in the range we are overwriting, which creates a delayed ref for
|
|
* that freed extent. This however is not reclaimed until the transaction
|
|
* commits, thus the next stages.
|
|
*
|
|
* RUN_DELAYED_IPUTS
|
|
* If we are freeing inodes, we want to make sure all delayed iputs have
|
|
* completed, because they could have been on an inode with i_nlink == 0, and
|
|
* thus have been truncated and freed up space. But again this space is not
|
|
* immediately re-usable, it comes in the form of a delayed ref, which must be
|
|
* run and then the transaction must be committed.
|
|
*
|
|
* FLUSH_DELAYED_REFS
|
|
* The above two cases generate delayed refs that will affect
|
|
* ->total_bytes_pinned. However this counter can be inconsistent with
|
|
* reality if there are outstanding delayed refs. This is because we adjust
|
|
* the counter based solely on the current set of delayed refs and disregard
|
|
* any on-disk state which might include more refs. So for example, if we
|
|
* have an extent with 2 references, but we only drop 1, we'll see that there
|
|
* is a negative delayed ref count for the extent and assume that the space
|
|
* will be freed, and thus increase ->total_bytes_pinned.
|
|
*
|
|
* Running the delayed refs gives us the actual real view of what will be
|
|
* freed at the transaction commit time. This stage will not actually free
|
|
* space for us, it just makes sure that may_commit_transaction() has all of
|
|
* the information it needs to make the right decision.
|
|
*
|
|
* COMMIT_TRANS
|
|
* This is where we reclaim all of the pinned space generated by the previous
|
|
* two stages. We will not commit the transaction if we don't think we're
|
|
* likely to satisfy our request, which means if our current free space +
|
|
* total_bytes_pinned < reservation we will not commit. This is why the
|
|
* previous states are actually important, to make sure we know for sure
|
|
* whether committing the transaction will allow us to make progress.
|
|
*
|
|
* ALLOC_CHUNK_FORCE
|
|
* For data we start with alloc chunk force, however we could have been full
|
|
* before, and then the transaction commit could have freed new block groups,
|
|
* so if we now have space to allocate do the force chunk allocation.
|
|
*/
|
|
static const enum btrfs_flush_state data_flush_states[] = {
|
|
FLUSH_DELALLOC_WAIT,
|
|
RUN_DELAYED_IPUTS,
|
|
FLUSH_DELAYED_REFS,
|
|
COMMIT_TRANS,
|
|
ALLOC_CHUNK_FORCE,
|
|
};
|
|
|
|
static void btrfs_async_reclaim_data_space(struct work_struct *work)
|
|
{
|
|
struct btrfs_fs_info *fs_info;
|
|
struct btrfs_space_info *space_info;
|
|
u64 last_tickets_id;
|
|
int flush_state = 0;
|
|
|
|
fs_info = container_of(work, struct btrfs_fs_info, async_data_reclaim_work);
|
|
space_info = fs_info->data_sinfo;
|
|
|
|
spin_lock(&space_info->lock);
|
|
if (list_empty(&space_info->tickets)) {
|
|
space_info->flush = 0;
|
|
spin_unlock(&space_info->lock);
|
|
return;
|
|
}
|
|
last_tickets_id = space_info->tickets_id;
|
|
spin_unlock(&space_info->lock);
|
|
|
|
while (!space_info->full) {
|
|
flush_space(fs_info, space_info, U64_MAX, ALLOC_CHUNK_FORCE);
|
|
spin_lock(&space_info->lock);
|
|
if (list_empty(&space_info->tickets)) {
|
|
space_info->flush = 0;
|
|
spin_unlock(&space_info->lock);
|
|
return;
|
|
}
|
|
last_tickets_id = space_info->tickets_id;
|
|
spin_unlock(&space_info->lock);
|
|
}
|
|
|
|
while (flush_state < ARRAY_SIZE(data_flush_states)) {
|
|
flush_space(fs_info, space_info, U64_MAX,
|
|
data_flush_states[flush_state]);
|
|
spin_lock(&space_info->lock);
|
|
if (list_empty(&space_info->tickets)) {
|
|
space_info->flush = 0;
|
|
spin_unlock(&space_info->lock);
|
|
return;
|
|
}
|
|
|
|
if (last_tickets_id == space_info->tickets_id) {
|
|
flush_state++;
|
|
} else {
|
|
last_tickets_id = space_info->tickets_id;
|
|
flush_state = 0;
|
|
}
|
|
|
|
if (flush_state >= ARRAY_SIZE(data_flush_states)) {
|
|
if (space_info->full) {
|
|
if (maybe_fail_all_tickets(fs_info, space_info))
|
|
flush_state = 0;
|
|
else
|
|
space_info->flush = 0;
|
|
} else {
|
|
flush_state = 0;
|
|
}
|
|
}
|
|
spin_unlock(&space_info->lock);
|
|
}
|
|
}
|
|
|
|
void btrfs_init_async_reclaim_work(struct btrfs_fs_info *fs_info)
|
|
{
|
|
INIT_WORK(&fs_info->async_reclaim_work, btrfs_async_reclaim_metadata_space);
|
|
INIT_WORK(&fs_info->async_data_reclaim_work, btrfs_async_reclaim_data_space);
|
|
}
|
|
|
|
static const enum btrfs_flush_state priority_flush_states[] = {
|
|
FLUSH_DELAYED_ITEMS_NR,
|
|
FLUSH_DELAYED_ITEMS,
|
|
ALLOC_CHUNK,
|
|
};
|
|
|
|
static const enum btrfs_flush_state evict_flush_states[] = {
|
|
FLUSH_DELAYED_ITEMS_NR,
|
|
FLUSH_DELAYED_ITEMS,
|
|
FLUSH_DELAYED_REFS_NR,
|
|
FLUSH_DELAYED_REFS,
|
|
FLUSH_DELALLOC,
|
|
FLUSH_DELALLOC_WAIT,
|
|
ALLOC_CHUNK,
|
|
COMMIT_TRANS,
|
|
};
|
|
|
|
static void priority_reclaim_metadata_space(struct btrfs_fs_info *fs_info,
|
|
struct btrfs_space_info *space_info,
|
|
struct reserve_ticket *ticket,
|
|
const enum btrfs_flush_state *states,
|
|
int states_nr)
|
|
{
|
|
u64 to_reclaim;
|
|
int flush_state;
|
|
|
|
spin_lock(&space_info->lock);
|
|
to_reclaim = btrfs_calc_reclaim_metadata_size(fs_info, space_info);
|
|
if (!to_reclaim) {
|
|
spin_unlock(&space_info->lock);
|
|
return;
|
|
}
|
|
spin_unlock(&space_info->lock);
|
|
|
|
flush_state = 0;
|
|
do {
|
|
flush_space(fs_info, space_info, to_reclaim, states[flush_state]);
|
|
flush_state++;
|
|
spin_lock(&space_info->lock);
|
|
if (ticket->bytes == 0) {
|
|
spin_unlock(&space_info->lock);
|
|
return;
|
|
}
|
|
spin_unlock(&space_info->lock);
|
|
} while (flush_state < states_nr);
|
|
}
|
|
|
|
static void priority_reclaim_data_space(struct btrfs_fs_info *fs_info,
|
|
struct btrfs_space_info *space_info,
|
|
struct reserve_ticket *ticket)
|
|
{
|
|
while (!space_info->full) {
|
|
flush_space(fs_info, space_info, U64_MAX, ALLOC_CHUNK_FORCE);
|
|
spin_lock(&space_info->lock);
|
|
if (ticket->bytes == 0) {
|
|
spin_unlock(&space_info->lock);
|
|
return;
|
|
}
|
|
spin_unlock(&space_info->lock);
|
|
}
|
|
}
|
|
|
|
static void wait_reserve_ticket(struct btrfs_fs_info *fs_info,
|
|
struct btrfs_space_info *space_info,
|
|
struct reserve_ticket *ticket)
|
|
|
|
{
|
|
DEFINE_WAIT(wait);
|
|
int ret = 0;
|
|
|
|
spin_lock(&space_info->lock);
|
|
while (ticket->bytes > 0 && ticket->error == 0) {
|
|
ret = prepare_to_wait_event(&ticket->wait, &wait, TASK_KILLABLE);
|
|
if (ret) {
|
|
/*
|
|
* Delete us from the list. After we unlock the space
|
|
* info, we don't want the async reclaim job to reserve
|
|
* space for this ticket. If that would happen, then the
|
|
* ticket's task would not known that space was reserved
|
|
* despite getting an error, resulting in a space leak
|
|
* (bytes_may_use counter of our space_info).
|
|
*/
|
|
remove_ticket(space_info, ticket);
|
|
ticket->error = -EINTR;
|
|
break;
|
|
}
|
|
spin_unlock(&space_info->lock);
|
|
|
|
schedule();
|
|
|
|
finish_wait(&ticket->wait, &wait);
|
|
spin_lock(&space_info->lock);
|
|
}
|
|
spin_unlock(&space_info->lock);
|
|
}
|
|
|
|
/**
|
|
* Do the appropriate flushing and waiting for a ticket
|
|
*
|
|
* @fs_info: the filesystem
|
|
* @space_info: space info for the reservation
|
|
* @ticket: ticket for the reservation
|
|
* @flush: how much we can flush
|
|
*
|
|
* This does the work of figuring out how to flush for the ticket, waiting for
|
|
* the reservation, and returning the appropriate error if there is one.
|
|
*/
|
|
static int handle_reserve_ticket(struct btrfs_fs_info *fs_info,
|
|
struct btrfs_space_info *space_info,
|
|
struct reserve_ticket *ticket,
|
|
enum btrfs_reserve_flush_enum flush)
|
|
{
|
|
int ret;
|
|
|
|
switch (flush) {
|
|
case BTRFS_RESERVE_FLUSH_DATA:
|
|
case BTRFS_RESERVE_FLUSH_ALL:
|
|
case BTRFS_RESERVE_FLUSH_ALL_STEAL:
|
|
wait_reserve_ticket(fs_info, space_info, ticket);
|
|
break;
|
|
case BTRFS_RESERVE_FLUSH_LIMIT:
|
|
priority_reclaim_metadata_space(fs_info, space_info, ticket,
|
|
priority_flush_states,
|
|
ARRAY_SIZE(priority_flush_states));
|
|
break;
|
|
case BTRFS_RESERVE_FLUSH_EVICT:
|
|
priority_reclaim_metadata_space(fs_info, space_info, ticket,
|
|
evict_flush_states,
|
|
ARRAY_SIZE(evict_flush_states));
|
|
break;
|
|
case BTRFS_RESERVE_FLUSH_FREE_SPACE_INODE:
|
|
priority_reclaim_data_space(fs_info, space_info, ticket);
|
|
break;
|
|
default:
|
|
ASSERT(0);
|
|
break;
|
|
}
|
|
|
|
spin_lock(&space_info->lock);
|
|
ret = ticket->error;
|
|
if (ticket->bytes || ticket->error) {
|
|
/*
|
|
* We were a priority ticket, so we need to delete ourselves
|
|
* from the list. Because we could have other priority tickets
|
|
* behind us that require less space, run
|
|
* btrfs_try_granting_tickets() to see if their reservations can
|
|
* now be made.
|
|
*/
|
|
if (!list_empty(&ticket->list)) {
|
|
remove_ticket(space_info, ticket);
|
|
btrfs_try_granting_tickets(fs_info, space_info);
|
|
}
|
|
|
|
if (!ret)
|
|
ret = -ENOSPC;
|
|
}
|
|
spin_unlock(&space_info->lock);
|
|
ASSERT(list_empty(&ticket->list));
|
|
/*
|
|
* Check that we can't have an error set if the reservation succeeded,
|
|
* as that would confuse tasks and lead them to error out without
|
|
* releasing reserved space (if an error happens the expectation is that
|
|
* space wasn't reserved at all).
|
|
*/
|
|
ASSERT(!(ticket->bytes == 0 && ticket->error));
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* This returns true if this flush state will go through the ordinary flushing
|
|
* code.
|
|
*/
|
|
static inline bool is_normal_flushing(enum btrfs_reserve_flush_enum flush)
|
|
{
|
|
return (flush == BTRFS_RESERVE_FLUSH_ALL) ||
|
|
(flush == BTRFS_RESERVE_FLUSH_ALL_STEAL);
|
|
}
|
|
|
|
/**
|
|
* Try to reserve bytes from the block_rsv's space
|
|
*
|
|
* @fs_info: the filesystem
|
|
* @space_info: space info we want to allocate from
|
|
* @orig_bytes: number of bytes we want
|
|
* @flush: whether or not we can flush to make our reservation
|
|
*
|
|
* This will reserve orig_bytes number of bytes from the space info associated
|
|
* with the block_rsv. If there is not enough space it will make an attempt to
|
|
* flush out space to make room. It will do this by flushing delalloc if
|
|
* possible or committing the transaction. If flush is 0 then no attempts to
|
|
* regain reservations will be made and this will fail if there is not enough
|
|
* space already.
|
|
*/
|
|
static int __reserve_bytes(struct btrfs_fs_info *fs_info,
|
|
struct btrfs_space_info *space_info, u64 orig_bytes,
|
|
enum btrfs_reserve_flush_enum flush)
|
|
{
|
|
struct work_struct *async_work;
|
|
struct reserve_ticket ticket;
|
|
u64 used;
|
|
int ret = 0;
|
|
bool pending_tickets;
|
|
|
|
ASSERT(orig_bytes);
|
|
ASSERT(!current->journal_info || flush != BTRFS_RESERVE_FLUSH_ALL);
|
|
|
|
if (flush == BTRFS_RESERVE_FLUSH_DATA)
|
|
async_work = &fs_info->async_data_reclaim_work;
|
|
else
|
|
async_work = &fs_info->async_reclaim_work;
|
|
|
|
spin_lock(&space_info->lock);
|
|
ret = -ENOSPC;
|
|
used = btrfs_space_info_used(space_info, true);
|
|
|
|
/*
|
|
* We don't want NO_FLUSH allocations to jump everybody, they can
|
|
* generally handle ENOSPC in a different way, so treat them the same as
|
|
* normal flushers when it comes to skipping pending tickets.
|
|
*/
|
|
if (is_normal_flushing(flush) || (flush == BTRFS_RESERVE_NO_FLUSH))
|
|
pending_tickets = !list_empty(&space_info->tickets) ||
|
|
!list_empty(&space_info->priority_tickets);
|
|
else
|
|
pending_tickets = !list_empty(&space_info->priority_tickets);
|
|
|
|
/*
|
|
* Carry on if we have enough space (short-circuit) OR call
|
|
* can_overcommit() to ensure we can overcommit to continue.
|
|
*/
|
|
if (!pending_tickets &&
|
|
((used + orig_bytes <= space_info->total_bytes) ||
|
|
btrfs_can_overcommit(fs_info, space_info, orig_bytes, flush))) {
|
|
btrfs_space_info_update_bytes_may_use(fs_info, space_info,
|
|
orig_bytes);
|
|
ret = 0;
|
|
}
|
|
|
|
/*
|
|
* If we couldn't make a reservation then setup our reservation ticket
|
|
* and kick the async worker if it's not already running.
|
|
*
|
|
* If we are a priority flusher then we just need to add our ticket to
|
|
* the list and we will do our own flushing further down.
|
|
*/
|
|
if (ret && flush != BTRFS_RESERVE_NO_FLUSH) {
|
|
ticket.bytes = orig_bytes;
|
|
ticket.error = 0;
|
|
space_info->reclaim_size += ticket.bytes;
|
|
init_waitqueue_head(&ticket.wait);
|
|
ticket.steal = (flush == BTRFS_RESERVE_FLUSH_ALL_STEAL);
|
|
if (flush == BTRFS_RESERVE_FLUSH_ALL ||
|
|
flush == BTRFS_RESERVE_FLUSH_ALL_STEAL ||
|
|
flush == BTRFS_RESERVE_FLUSH_DATA) {
|
|
list_add_tail(&ticket.list, &space_info->tickets);
|
|
if (!space_info->flush) {
|
|
space_info->flush = 1;
|
|
trace_btrfs_trigger_flush(fs_info,
|
|
space_info->flags,
|
|
orig_bytes, flush,
|
|
"enospc");
|
|
queue_work(system_unbound_wq, async_work);
|
|
}
|
|
} else {
|
|
list_add_tail(&ticket.list,
|
|
&space_info->priority_tickets);
|
|
}
|
|
} else if (!ret && space_info->flags & BTRFS_BLOCK_GROUP_METADATA) {
|
|
used += orig_bytes;
|
|
/*
|
|
* We will do the space reservation dance during log replay,
|
|
* which means we won't have fs_info->fs_root set, so don't do
|
|
* the async reclaim as we will panic.
|
|
*/
|
|
if (!test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags) &&
|
|
need_do_async_reclaim(fs_info, space_info, used) &&
|
|
!work_busy(&fs_info->async_reclaim_work)) {
|
|
trace_btrfs_trigger_flush(fs_info, space_info->flags,
|
|
orig_bytes, flush, "preempt");
|
|
queue_work(system_unbound_wq,
|
|
&fs_info->async_reclaim_work);
|
|
}
|
|
}
|
|
spin_unlock(&space_info->lock);
|
|
if (!ret || flush == BTRFS_RESERVE_NO_FLUSH)
|
|
return ret;
|
|
|
|
return handle_reserve_ticket(fs_info, space_info, &ticket, flush);
|
|
}
|
|
|
|
/**
|
|
* Trye to reserve metadata bytes from the block_rsv's space
|
|
*
|
|
* @root: the root we're allocating for
|
|
* @block_rsv: block_rsv we're allocating for
|
|
* @orig_bytes: number of bytes we want
|
|
* @flush: whether or not we can flush to make our reservation
|
|
*
|
|
* This will reserve orig_bytes number of bytes from the space info associated
|
|
* with the block_rsv. If there is not enough space it will make an attempt to
|
|
* flush out space to make room. It will do this by flushing delalloc if
|
|
* possible or committing the transaction. If flush is 0 then no attempts to
|
|
* regain reservations will be made and this will fail if there is not enough
|
|
* space already.
|
|
*/
|
|
int btrfs_reserve_metadata_bytes(struct btrfs_root *root,
|
|
struct btrfs_block_rsv *block_rsv,
|
|
u64 orig_bytes,
|
|
enum btrfs_reserve_flush_enum flush)
|
|
{
|
|
struct btrfs_fs_info *fs_info = root->fs_info;
|
|
struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
|
|
int ret;
|
|
|
|
ret = __reserve_bytes(fs_info, block_rsv->space_info, orig_bytes, flush);
|
|
if (ret == -ENOSPC &&
|
|
unlikely(root->orphan_cleanup_state == ORPHAN_CLEANUP_STARTED)) {
|
|
if (block_rsv != global_rsv &&
|
|
!btrfs_block_rsv_use_bytes(global_rsv, orig_bytes))
|
|
ret = 0;
|
|
}
|
|
if (ret == -ENOSPC) {
|
|
trace_btrfs_space_reservation(fs_info, "space_info:enospc",
|
|
block_rsv->space_info->flags,
|
|
orig_bytes, 1);
|
|
|
|
if (btrfs_test_opt(fs_info, ENOSPC_DEBUG))
|
|
btrfs_dump_space_info(fs_info, block_rsv->space_info,
|
|
orig_bytes, 0);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* Try to reserve data bytes for an allocation
|
|
*
|
|
* @fs_info: the filesystem
|
|
* @bytes: number of bytes we need
|
|
* @flush: how we are allowed to flush
|
|
*
|
|
* This will reserve bytes from the data space info. If there is not enough
|
|
* space then we will attempt to flush space as specified by flush.
|
|
*/
|
|
int btrfs_reserve_data_bytes(struct btrfs_fs_info *fs_info, u64 bytes,
|
|
enum btrfs_reserve_flush_enum flush)
|
|
{
|
|
struct btrfs_space_info *data_sinfo = fs_info->data_sinfo;
|
|
int ret;
|
|
|
|
ASSERT(flush == BTRFS_RESERVE_FLUSH_DATA ||
|
|
flush == BTRFS_RESERVE_FLUSH_FREE_SPACE_INODE);
|
|
ASSERT(!current->journal_info || flush != BTRFS_RESERVE_FLUSH_DATA);
|
|
|
|
ret = __reserve_bytes(fs_info, data_sinfo, bytes, flush);
|
|
if (ret == -ENOSPC) {
|
|
trace_btrfs_space_reservation(fs_info, "space_info:enospc",
|
|
data_sinfo->flags, bytes, 1);
|
|
if (btrfs_test_opt(fs_info, ENOSPC_DEBUG))
|
|
btrfs_dump_space_info(fs_info, data_sinfo, bytes, 0);
|
|
}
|
|
return ret;
|
|
}
|