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// SPDX-License-Identifier: GPL-2.0
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/*
* Copyright ( C ) 2007 Oracle . All rights reserved .
*/
# include <linux/slab.h>
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# include <linux/blkdev.h>
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# include <linux/writeback.h>
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# include <linux/sched/mm.h>
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# include "misc.h"
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# include "ctree.h"
# include "transaction.h"
# include "btrfs_inode.h"
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# include "extent_io.h"
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# include "disk-io.h"
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# include "compression.h"
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# include "delalloc-space.h"
btrfs: change timing for qgroup reserved space for ordered extents to fix reserved space leak
[BUG]
The following simple workload from fsstress can lead to qgroup reserved
data space leak:
0/0: creat f0 x:0 0 0
0/0: creat add id=0,parent=-1
0/1: write f0[259 1 0 0 0 0] [600030,27288] 0
0/4: dwrite - xfsctl(XFS_IOC_DIOINFO) f0[259 1 0 0 64 627318] return 25, fallback to stat()
0/4: dwrite f0[259 1 0 0 64 627318] [610304,106496] 0
This would cause btrfs qgroup to leak 20480 bytes for data reserved
space. If btrfs qgroup limit is enabled, such leak can lead to
unexpected early EDQUOT and unusable space.
[CAUSE]
When doing direct IO, kernel will try to writeback existing buffered
page cache, then invalidate them:
generic_file_direct_write()
|- filemap_write_and_wait_range();
|- invalidate_inode_pages2_range();
However for btrfs, the bi_end_io hook doesn't finish all its heavy work
right after bio ends. In fact, it delays its work further:
submit_extent_page(end_io_func=end_bio_extent_writepage);
end_bio_extent_writepage()
|- btrfs_writepage_endio_finish_ordered()
|- btrfs_init_work(finish_ordered_fn);
<<< Work queue execution >>>
finish_ordered_fn()
|- btrfs_finish_ordered_io();
|- Clear qgroup bits
This means, when filemap_write_and_wait_range() returns,
btrfs_finish_ordered_io() is not guaranteed to be executed, thus the
qgroup bits for related range are not cleared.
Now into how the leak happens, this will only focus on the overlapping
part of buffered and direct IO part.
1. After buffered write
The inode had the following range with QGROUP_RESERVED bit:
596 616K
|///////////////|
Qgroup reserved data space: 20K
2. Writeback part for range [596K, 616K)
Write back finished, but btrfs_finish_ordered_io() not get called
yet.
So we still have:
596K 616K
|///////////////|
Qgroup reserved data space: 20K
3. Pages for range [596K, 616K) get released
This will clear all qgroup bits, but don't update the reserved data
space.
So we have:
596K 616K
| |
Qgroup reserved data space: 20K
That number doesn't match the qgroup bit range anymore.
4. Dio prepare space for range [596K, 700K)
Qgroup reserved data space for that range, we got:
596K 616K 700K
|///////////////|///////////////////////|
Qgroup reserved data space: 20K + 104K = 124K
5. btrfs_finish_ordered_range() gets executed for range [596K, 616K)
Qgroup free reserved space for that range, we got:
596K 616K 700K
| |///////////////////////|
We need to free that range of reserved space.
Qgroup reserved data space: 124K - 20K = 104K
6. btrfs_finish_ordered_range() gets executed for range [596K, 700K)
However qgroup bit for range [596K, 616K) is already cleared in
previous step, so we only free 84K for qgroup reserved space.
596K 616K 700K
| | |
We need to free that range of reserved space.
Qgroup reserved data space: 104K - 84K = 20K
Now there is no way to release that 20K unless disabling qgroup or
unmounting the fs.
[FIX]
This patch will change the timing of btrfs_qgroup_release/free_data()
call. Here it uses buffered COW write as an example.
The new timing | The old timing
----------------------------------------+---------------------------------------
btrfs_buffered_write() | btrfs_buffered_write()
|- btrfs_qgroup_reserve_data() | |- btrfs_qgroup_reserve_data()
|
btrfs_run_delalloc_range() | btrfs_run_delalloc_range()
|- btrfs_add_ordered_extent() |
|- btrfs_qgroup_release_data() |
The reserved is passed into |
btrfs_ordered_extent structure |
|
btrfs_finish_ordered_io() | btrfs_finish_ordered_io()
|- The reserved space is passed to | |- btrfs_qgroup_release_data()
btrfs_qgroup_record | The resereved space is passed
| to btrfs_qgroup_recrod
|
btrfs_qgroup_account_extents() | btrfs_qgroup_account_extents()
|- btrfs_qgroup_free_refroot() | |- btrfs_qgroup_free_refroot()
The point of such change is to ensure, when ordered extents are
submitted, the qgroup reserved space is already released, to keep the
timing aligned with file_write_and_wait_range().
So that qgroup data reserved space is all bound to btrfs_ordered_extent
and solve the timing mismatch.
Fixes: f695fdcef83a ("btrfs: qgroup: Introduce functions to release/free qgroup reserve data space")
Suggested-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-06-10 04:04:43 +03:00
# include "qgroup.h"
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static struct kmem_cache * btrfs_ordered_extent_cache ;
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static u64 entry_end ( struct btrfs_ordered_extent * entry )
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{
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if ( entry - > file_offset + entry - > num_bytes < entry - > file_offset )
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return ( u64 ) - 1 ;
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return entry - > file_offset + entry - > num_bytes ;
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}
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/* returns NULL if the insertion worked, or it returns the node it did find
* in the tree
*/
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static struct rb_node * tree_insert ( struct rb_root * root , u64 file_offset ,
struct rb_node * node )
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{
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struct rb_node * * p = & root - > rb_node ;
struct rb_node * parent = NULL ;
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struct btrfs_ordered_extent * entry ;
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while ( * p ) {
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parent = * p ;
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entry = rb_entry ( parent , struct btrfs_ordered_extent , rb_node ) ;
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if ( file_offset < entry - > file_offset )
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p = & ( * p ) - > rb_left ;
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else if ( file_offset > = entry_end ( entry ) )
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p = & ( * p ) - > rb_right ;
else
return parent ;
}
rb_link_node ( node , parent , p ) ;
rb_insert_color ( node , root ) ;
return NULL ;
}
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/*
* look for a given offset in the tree , and if it can ' t be found return the
* first lesser offset
*/
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static struct rb_node * __tree_search ( struct rb_root * root , u64 file_offset ,
struct rb_node * * prev_ret )
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{
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struct rb_node * n = root - > rb_node ;
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struct rb_node * prev = NULL ;
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struct rb_node * test ;
struct btrfs_ordered_extent * entry ;
struct btrfs_ordered_extent * prev_entry = NULL ;
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while ( n ) {
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entry = rb_entry ( n , struct btrfs_ordered_extent , rb_node ) ;
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prev = n ;
prev_entry = entry ;
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if ( file_offset < entry - > file_offset )
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n = n - > rb_left ;
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else if ( file_offset > = entry_end ( entry ) )
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n = n - > rb_right ;
else
return n ;
}
if ( ! prev_ret )
return NULL ;
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while ( prev & & file_offset > = entry_end ( prev_entry ) ) {
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test = rb_next ( prev ) ;
if ( ! test )
break ;
prev_entry = rb_entry ( test , struct btrfs_ordered_extent ,
rb_node ) ;
if ( file_offset < entry_end ( prev_entry ) )
break ;
prev = test ;
}
if ( prev )
prev_entry = rb_entry ( prev , struct btrfs_ordered_extent ,
rb_node ) ;
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while ( prev & & file_offset < entry_end ( prev_entry ) ) {
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test = rb_prev ( prev ) ;
if ( ! test )
break ;
prev_entry = rb_entry ( test , struct btrfs_ordered_extent ,
rb_node ) ;
prev = test ;
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}
* prev_ret = prev ;
return NULL ;
}
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/*
* helper to check if a given offset is inside a given entry
*/
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static int offset_in_entry ( struct btrfs_ordered_extent * entry , u64 file_offset )
{
if ( file_offset < entry - > file_offset | |
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entry - > file_offset + entry - > num_bytes < = file_offset )
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return 0 ;
return 1 ;
}
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static int range_overlaps ( struct btrfs_ordered_extent * entry , u64 file_offset ,
u64 len )
{
if ( file_offset + len < = entry - > file_offset | |
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entry - > file_offset + entry - > num_bytes < = file_offset )
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return 0 ;
return 1 ;
}
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/*
* look find the first ordered struct that has this offset , otherwise
* the first one less than this offset
*/
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static inline struct rb_node * tree_search ( struct btrfs_ordered_inode_tree * tree ,
u64 file_offset )
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{
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struct rb_root * root = & tree - > tree ;
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struct rb_node * prev = NULL ;
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struct rb_node * ret ;
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struct btrfs_ordered_extent * entry ;
if ( tree - > last ) {
entry = rb_entry ( tree - > last , struct btrfs_ordered_extent ,
rb_node ) ;
if ( offset_in_entry ( entry , file_offset ) )
return tree - > last ;
}
ret = __tree_search ( root , file_offset , & prev ) ;
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if ( ! ret )
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ret = prev ;
if ( ret )
tree - > last = ret ;
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return ret ;
}
btrfs: change timing for qgroup reserved space for ordered extents to fix reserved space leak
[BUG]
The following simple workload from fsstress can lead to qgroup reserved
data space leak:
0/0: creat f0 x:0 0 0
0/0: creat add id=0,parent=-1
0/1: write f0[259 1 0 0 0 0] [600030,27288] 0
0/4: dwrite - xfsctl(XFS_IOC_DIOINFO) f0[259 1 0 0 64 627318] return 25, fallback to stat()
0/4: dwrite f0[259 1 0 0 64 627318] [610304,106496] 0
This would cause btrfs qgroup to leak 20480 bytes for data reserved
space. If btrfs qgroup limit is enabled, such leak can lead to
unexpected early EDQUOT and unusable space.
[CAUSE]
When doing direct IO, kernel will try to writeback existing buffered
page cache, then invalidate them:
generic_file_direct_write()
|- filemap_write_and_wait_range();
|- invalidate_inode_pages2_range();
However for btrfs, the bi_end_io hook doesn't finish all its heavy work
right after bio ends. In fact, it delays its work further:
submit_extent_page(end_io_func=end_bio_extent_writepage);
end_bio_extent_writepage()
|- btrfs_writepage_endio_finish_ordered()
|- btrfs_init_work(finish_ordered_fn);
<<< Work queue execution >>>
finish_ordered_fn()
|- btrfs_finish_ordered_io();
|- Clear qgroup bits
This means, when filemap_write_and_wait_range() returns,
btrfs_finish_ordered_io() is not guaranteed to be executed, thus the
qgroup bits for related range are not cleared.
Now into how the leak happens, this will only focus on the overlapping
part of buffered and direct IO part.
1. After buffered write
The inode had the following range with QGROUP_RESERVED bit:
596 616K
|///////////////|
Qgroup reserved data space: 20K
2. Writeback part for range [596K, 616K)
Write back finished, but btrfs_finish_ordered_io() not get called
yet.
So we still have:
596K 616K
|///////////////|
Qgroup reserved data space: 20K
3. Pages for range [596K, 616K) get released
This will clear all qgroup bits, but don't update the reserved data
space.
So we have:
596K 616K
| |
Qgroup reserved data space: 20K
That number doesn't match the qgroup bit range anymore.
4. Dio prepare space for range [596K, 700K)
Qgroup reserved data space for that range, we got:
596K 616K 700K
|///////////////|///////////////////////|
Qgroup reserved data space: 20K + 104K = 124K
5. btrfs_finish_ordered_range() gets executed for range [596K, 616K)
Qgroup free reserved space for that range, we got:
596K 616K 700K
| |///////////////////////|
We need to free that range of reserved space.
Qgroup reserved data space: 124K - 20K = 104K
6. btrfs_finish_ordered_range() gets executed for range [596K, 700K)
However qgroup bit for range [596K, 616K) is already cleared in
previous step, so we only free 84K for qgroup reserved space.
596K 616K 700K
| | |
We need to free that range of reserved space.
Qgroup reserved data space: 104K - 84K = 20K
Now there is no way to release that 20K unless disabling qgroup or
unmounting the fs.
[FIX]
This patch will change the timing of btrfs_qgroup_release/free_data()
call. Here it uses buffered COW write as an example.
The new timing | The old timing
----------------------------------------+---------------------------------------
btrfs_buffered_write() | btrfs_buffered_write()
|- btrfs_qgroup_reserve_data() | |- btrfs_qgroup_reserve_data()
|
btrfs_run_delalloc_range() | btrfs_run_delalloc_range()
|- btrfs_add_ordered_extent() |
|- btrfs_qgroup_release_data() |
The reserved is passed into |
btrfs_ordered_extent structure |
|
btrfs_finish_ordered_io() | btrfs_finish_ordered_io()
|- The reserved space is passed to | |- btrfs_qgroup_release_data()
btrfs_qgroup_record | The resereved space is passed
| to btrfs_qgroup_recrod
|
btrfs_qgroup_account_extents() | btrfs_qgroup_account_extents()
|- btrfs_qgroup_free_refroot() | |- btrfs_qgroup_free_refroot()
The point of such change is to ensure, when ordered extents are
submitted, the qgroup reserved space is already released, to keep the
timing aligned with file_write_and_wait_range().
So that qgroup data reserved space is all bound to btrfs_ordered_extent
and solve the timing mismatch.
Fixes: f695fdcef83a ("btrfs: qgroup: Introduce functions to release/free qgroup reserve data space")
Suggested-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-06-10 04:04:43 +03:00
/*
* Allocate and add a new ordered_extent into the per - inode tree .
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*
* The tree is given a single reference on the ordered extent that was
* inserted .
*/
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static int __btrfs_add_ordered_extent ( struct inode * inode , u64 file_offset ,
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u64 disk_bytenr , u64 num_bytes ,
u64 disk_num_bytes , int type , int dio ,
int compress_type )
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{
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struct btrfs_fs_info * fs_info = btrfs_sb ( inode - > i_sb ) ;
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struct btrfs_root * root = BTRFS_I ( inode ) - > root ;
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struct btrfs_ordered_inode_tree * tree ;
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struct rb_node * node ;
struct btrfs_ordered_extent * entry ;
btrfs: change timing for qgroup reserved space for ordered extents to fix reserved space leak
[BUG]
The following simple workload from fsstress can lead to qgroup reserved
data space leak:
0/0: creat f0 x:0 0 0
0/0: creat add id=0,parent=-1
0/1: write f0[259 1 0 0 0 0] [600030,27288] 0
0/4: dwrite - xfsctl(XFS_IOC_DIOINFO) f0[259 1 0 0 64 627318] return 25, fallback to stat()
0/4: dwrite f0[259 1 0 0 64 627318] [610304,106496] 0
This would cause btrfs qgroup to leak 20480 bytes for data reserved
space. If btrfs qgroup limit is enabled, such leak can lead to
unexpected early EDQUOT and unusable space.
[CAUSE]
When doing direct IO, kernel will try to writeback existing buffered
page cache, then invalidate them:
generic_file_direct_write()
|- filemap_write_and_wait_range();
|- invalidate_inode_pages2_range();
However for btrfs, the bi_end_io hook doesn't finish all its heavy work
right after bio ends. In fact, it delays its work further:
submit_extent_page(end_io_func=end_bio_extent_writepage);
end_bio_extent_writepage()
|- btrfs_writepage_endio_finish_ordered()
|- btrfs_init_work(finish_ordered_fn);
<<< Work queue execution >>>
finish_ordered_fn()
|- btrfs_finish_ordered_io();
|- Clear qgroup bits
This means, when filemap_write_and_wait_range() returns,
btrfs_finish_ordered_io() is not guaranteed to be executed, thus the
qgroup bits for related range are not cleared.
Now into how the leak happens, this will only focus on the overlapping
part of buffered and direct IO part.
1. After buffered write
The inode had the following range with QGROUP_RESERVED bit:
596 616K
|///////////////|
Qgroup reserved data space: 20K
2. Writeback part for range [596K, 616K)
Write back finished, but btrfs_finish_ordered_io() not get called
yet.
So we still have:
596K 616K
|///////////////|
Qgroup reserved data space: 20K
3. Pages for range [596K, 616K) get released
This will clear all qgroup bits, but don't update the reserved data
space.
So we have:
596K 616K
| |
Qgroup reserved data space: 20K
That number doesn't match the qgroup bit range anymore.
4. Dio prepare space for range [596K, 700K)
Qgroup reserved data space for that range, we got:
596K 616K 700K
|///////////////|///////////////////////|
Qgroup reserved data space: 20K + 104K = 124K
5. btrfs_finish_ordered_range() gets executed for range [596K, 616K)
Qgroup free reserved space for that range, we got:
596K 616K 700K
| |///////////////////////|
We need to free that range of reserved space.
Qgroup reserved data space: 124K - 20K = 104K
6. btrfs_finish_ordered_range() gets executed for range [596K, 700K)
However qgroup bit for range [596K, 616K) is already cleared in
previous step, so we only free 84K for qgroup reserved space.
596K 616K 700K
| | |
We need to free that range of reserved space.
Qgroup reserved data space: 104K - 84K = 20K
Now there is no way to release that 20K unless disabling qgroup or
unmounting the fs.
[FIX]
This patch will change the timing of btrfs_qgroup_release/free_data()
call. Here it uses buffered COW write as an example.
The new timing | The old timing
----------------------------------------+---------------------------------------
btrfs_buffered_write() | btrfs_buffered_write()
|- btrfs_qgroup_reserve_data() | |- btrfs_qgroup_reserve_data()
|
btrfs_run_delalloc_range() | btrfs_run_delalloc_range()
|- btrfs_add_ordered_extent() |
|- btrfs_qgroup_release_data() |
The reserved is passed into |
btrfs_ordered_extent structure |
|
btrfs_finish_ordered_io() | btrfs_finish_ordered_io()
|- The reserved space is passed to | |- btrfs_qgroup_release_data()
btrfs_qgroup_record | The resereved space is passed
| to btrfs_qgroup_recrod
|
btrfs_qgroup_account_extents() | btrfs_qgroup_account_extents()
|- btrfs_qgroup_free_refroot() | |- btrfs_qgroup_free_refroot()
The point of such change is to ensure, when ordered extents are
submitted, the qgroup reserved space is already released, to keep the
timing aligned with file_write_and_wait_range().
So that qgroup data reserved space is all bound to btrfs_ordered_extent
and solve the timing mismatch.
Fixes: f695fdcef83a ("btrfs: qgroup: Introduce functions to release/free qgroup reserve data space")
Suggested-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-06-10 04:04:43 +03:00
int ret ;
if ( type = = BTRFS_ORDERED_NOCOW | | type = = BTRFS_ORDERED_PREALLOC ) {
/* For nocow write, we can release the qgroup rsv right now */
ret = btrfs_qgroup_free_data ( inode , NULL , file_offset ,
num_bytes ) ;
if ( ret < 0 )
return ret ;
ret = 0 ;
} else {
/*
* The ordered extent has reserved qgroup space , release now
* and pass the reserved number for qgroup_record to free .
*/
ret = btrfs_qgroup_release_data ( inode , file_offset , num_bytes ) ;
if ( ret < 0 )
return ret ;
}
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tree = & BTRFS_I ( inode ) - > ordered_tree ;
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entry = kmem_cache_zalloc ( btrfs_ordered_extent_cache , GFP_NOFS ) ;
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if ( ! entry )
return - ENOMEM ;
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entry - > file_offset = file_offset ;
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entry - > disk_bytenr = disk_bytenr ;
entry - > num_bytes = num_bytes ;
entry - > disk_num_bytes = disk_num_bytes ;
entry - > bytes_left = num_bytes ;
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entry - > inode = igrab ( inode ) ;
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entry - > compress_type = compress_type ;
2013-08-29 21:57:21 +04:00
entry - > truncated_len = ( u64 ) - 1 ;
btrfs: change timing for qgroup reserved space for ordered extents to fix reserved space leak
[BUG]
The following simple workload from fsstress can lead to qgroup reserved
data space leak:
0/0: creat f0 x:0 0 0
0/0: creat add id=0,parent=-1
0/1: write f0[259 1 0 0 0 0] [600030,27288] 0
0/4: dwrite - xfsctl(XFS_IOC_DIOINFO) f0[259 1 0 0 64 627318] return 25, fallback to stat()
0/4: dwrite f0[259 1 0 0 64 627318] [610304,106496] 0
This would cause btrfs qgroup to leak 20480 bytes for data reserved
space. If btrfs qgroup limit is enabled, such leak can lead to
unexpected early EDQUOT and unusable space.
[CAUSE]
When doing direct IO, kernel will try to writeback existing buffered
page cache, then invalidate them:
generic_file_direct_write()
|- filemap_write_and_wait_range();
|- invalidate_inode_pages2_range();
However for btrfs, the bi_end_io hook doesn't finish all its heavy work
right after bio ends. In fact, it delays its work further:
submit_extent_page(end_io_func=end_bio_extent_writepage);
end_bio_extent_writepage()
|- btrfs_writepage_endio_finish_ordered()
|- btrfs_init_work(finish_ordered_fn);
<<< Work queue execution >>>
finish_ordered_fn()
|- btrfs_finish_ordered_io();
|- Clear qgroup bits
This means, when filemap_write_and_wait_range() returns,
btrfs_finish_ordered_io() is not guaranteed to be executed, thus the
qgroup bits for related range are not cleared.
Now into how the leak happens, this will only focus on the overlapping
part of buffered and direct IO part.
1. After buffered write
The inode had the following range with QGROUP_RESERVED bit:
596 616K
|///////////////|
Qgroup reserved data space: 20K
2. Writeback part for range [596K, 616K)
Write back finished, but btrfs_finish_ordered_io() not get called
yet.
So we still have:
596K 616K
|///////////////|
Qgroup reserved data space: 20K
3. Pages for range [596K, 616K) get released
This will clear all qgroup bits, but don't update the reserved data
space.
So we have:
596K 616K
| |
Qgroup reserved data space: 20K
That number doesn't match the qgroup bit range anymore.
4. Dio prepare space for range [596K, 700K)
Qgroup reserved data space for that range, we got:
596K 616K 700K
|///////////////|///////////////////////|
Qgroup reserved data space: 20K + 104K = 124K
5. btrfs_finish_ordered_range() gets executed for range [596K, 616K)
Qgroup free reserved space for that range, we got:
596K 616K 700K
| |///////////////////////|
We need to free that range of reserved space.
Qgroup reserved data space: 124K - 20K = 104K
6. btrfs_finish_ordered_range() gets executed for range [596K, 700K)
However qgroup bit for range [596K, 616K) is already cleared in
previous step, so we only free 84K for qgroup reserved space.
596K 616K 700K
| | |
We need to free that range of reserved space.
Qgroup reserved data space: 104K - 84K = 20K
Now there is no way to release that 20K unless disabling qgroup or
unmounting the fs.
[FIX]
This patch will change the timing of btrfs_qgroup_release/free_data()
call. Here it uses buffered COW write as an example.
The new timing | The old timing
----------------------------------------+---------------------------------------
btrfs_buffered_write() | btrfs_buffered_write()
|- btrfs_qgroup_reserve_data() | |- btrfs_qgroup_reserve_data()
|
btrfs_run_delalloc_range() | btrfs_run_delalloc_range()
|- btrfs_add_ordered_extent() |
|- btrfs_qgroup_release_data() |
The reserved is passed into |
btrfs_ordered_extent structure |
|
btrfs_finish_ordered_io() | btrfs_finish_ordered_io()
|- The reserved space is passed to | |- btrfs_qgroup_release_data()
btrfs_qgroup_record | The resereved space is passed
| to btrfs_qgroup_recrod
|
btrfs_qgroup_account_extents() | btrfs_qgroup_account_extents()
|- btrfs_qgroup_free_refroot() | |- btrfs_qgroup_free_refroot()
The point of such change is to ensure, when ordered extents are
submitted, the qgroup reserved space is already released, to keep the
timing aligned with file_write_and_wait_range().
So that qgroup data reserved space is all bound to btrfs_ordered_extent
and solve the timing mismatch.
Fixes: f695fdcef83a ("btrfs: qgroup: Introduce functions to release/free qgroup reserve data space")
Suggested-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-06-10 04:04:43 +03:00
entry - > qgroup_rsv = ret ;
2008-10-30 21:25:28 +03:00
if ( type ! = BTRFS_ORDERED_IO_DONE & & type ! = BTRFS_ORDERED_COMPLETE )
2008-10-30 21:20:02 +03:00
set_bit ( type , & entry - > flags ) ;
2008-07-24 19:57:52 +04:00
2019-04-10 22:56:09 +03:00
if ( dio ) {
2019-12-03 04:34:19 +03:00
percpu_counter_add_batch ( & fs_info - > dio_bytes , num_bytes ,
2019-04-10 22:56:09 +03:00
fs_info - > delalloc_batch ) ;
2010-05-23 19:00:55 +04:00
set_bit ( BTRFS_ORDERED_DIRECT , & entry - > flags ) ;
2019-04-10 22:56:09 +03:00
}
2010-05-23 19:00:55 +04:00
2008-07-17 20:53:50 +04:00
/* one ref for the tree */
2017-03-03 11:55:13 +03:00
refcount_set ( & entry - > refs , 1 ) ;
2008-07-17 20:53:50 +04:00
init_waitqueue_head ( & entry - > wait ) ;
INIT_LIST_HEAD ( & entry - > list ) ;
2008-07-24 19:57:52 +04:00
INIT_LIST_HEAD ( & entry - > root_extent_list ) ;
2012-10-25 13:41:36 +04:00
INIT_LIST_HEAD ( & entry - > work_list ) ;
init_completion ( & entry - > completion ) ;
2008-01-08 23:46:30 +03:00
Btrfs: add initial tracepoint support for btrfs
Tracepoints can provide insight into why btrfs hits bugs and be greatly
helpful for debugging, e.g
dd-7822 [000] 2121.641088: btrfs_inode_request: root = 5(FS_TREE), gen = 4, ino = 256, blocks = 8, disk_i_size = 0, last_trans = 8, logged_trans = 0
dd-7822 [000] 2121.641100: btrfs_inode_new: root = 5(FS_TREE), gen = 8, ino = 257, blocks = 0, disk_i_size = 0, last_trans = 0, logged_trans = 0
btrfs-transacti-7804 [001] 2146.935420: btrfs_cow_block: root = 2(EXTENT_TREE), refs = 2, orig_buf = 29368320 (orig_level = 0), cow_buf = 29388800 (cow_level = 0)
btrfs-transacti-7804 [001] 2146.935473: btrfs_cow_block: root = 1(ROOT_TREE), refs = 2, orig_buf = 29364224 (orig_level = 0), cow_buf = 29392896 (cow_level = 0)
btrfs-transacti-7804 [001] 2146.972221: btrfs_transaction_commit: root = 1(ROOT_TREE), gen = 8
flush-btrfs-2-7821 [001] 2155.824210: btrfs_chunk_alloc: root = 3(CHUNK_TREE), offset = 1103101952, size = 1073741824, num_stripes = 1, sub_stripes = 0, type = DATA
flush-btrfs-2-7821 [001] 2155.824241: btrfs_cow_block: root = 2(EXTENT_TREE), refs = 2, orig_buf = 29388800 (orig_level = 0), cow_buf = 29396992 (cow_level = 0)
flush-btrfs-2-7821 [001] 2155.824255: btrfs_cow_block: root = 4(DEV_TREE), refs = 2, orig_buf = 29372416 (orig_level = 0), cow_buf = 29401088 (cow_level = 0)
flush-btrfs-2-7821 [000] 2155.824329: btrfs_cow_block: root = 3(CHUNK_TREE), refs = 2, orig_buf = 20971520 (orig_level = 0), cow_buf = 20975616 (cow_level = 0)
btrfs-endio-wri-7800 [001] 2155.898019: btrfs_cow_block: root = 5(FS_TREE), refs = 2, orig_buf = 29384704 (orig_level = 0), cow_buf = 29405184 (cow_level = 0)
btrfs-endio-wri-7800 [001] 2155.898043: btrfs_cow_block: root = 7(CSUM_TREE), refs = 2, orig_buf = 29376512 (orig_level = 0), cow_buf = 29409280 (cow_level = 0)
Here is what I have added:
1) ordere_extent:
btrfs_ordered_extent_add
btrfs_ordered_extent_remove
btrfs_ordered_extent_start
btrfs_ordered_extent_put
These provide critical information to understand how ordered_extents are
updated.
2) extent_map:
btrfs_get_extent
extent_map is used in both read and write cases, and it is useful for tracking
how btrfs specific IO is running.
3) writepage:
__extent_writepage
btrfs_writepage_end_io_hook
Pages are cirtical resourses and produce a lot of corner cases during writeback,
so it is valuable to know how page is written to disk.
4) inode:
btrfs_inode_new
btrfs_inode_request
btrfs_inode_evict
These can show where and when a inode is created, when a inode is evicted.
5) sync:
btrfs_sync_file
btrfs_sync_fs
These show sync arguments.
6) transaction:
btrfs_transaction_commit
In transaction based filesystem, it will be useful to know the generation and
who does commit.
7) back reference and cow:
btrfs_delayed_tree_ref
btrfs_delayed_data_ref
btrfs_delayed_ref_head
btrfs_cow_block
Btrfs natively supports back references, these tracepoints are helpful on
understanding btrfs's COW mechanism.
8) chunk:
btrfs_chunk_alloc
btrfs_chunk_free
Chunk is a link between physical offset and logical offset, and stands for space
infomation in btrfs, and these are helpful on tracing space things.
9) reserved_extent:
btrfs_reserved_extent_alloc
btrfs_reserved_extent_free
These can show how btrfs uses its space.
Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-03-24 14:18:59 +03:00
trace_btrfs_ordered_extent_add ( inode , entry ) ;
2012-05-02 22:00:54 +04:00
spin_lock_irq ( & tree - > lock ) ;
2008-07-17 20:53:50 +04:00
node = tree_insert ( & tree - > tree , file_offset ,
& entry - > rb_node ) ;
2011-10-04 07:22:33 +04:00
if ( node )
2019-11-29 12:38:13 +03:00
btrfs_panic ( fs_info , - EEXIST ,
" inconsistency in ordered tree at offset %llu " ,
file_offset ) ;
2012-05-02 22:00:54 +04:00
spin_unlock_irq ( & tree - > lock ) ;
2009-01-06 05:25:51 +03:00
2013-05-15 11:48:23 +04:00
spin_lock ( & root - > ordered_extent_lock ) ;
2008-07-24 19:57:52 +04:00
list_add_tail ( & entry - > root_extent_list ,
2013-05-15 11:48:23 +04:00
& root - > ordered_extents ) ;
root - > nr_ordered_extents + + ;
if ( root - > nr_ordered_extents = = 1 ) {
2016-06-23 01:54:23 +03:00
spin_lock ( & fs_info - > ordered_root_lock ) ;
2013-05-15 11:48:23 +04:00
BUG_ON ( ! list_empty ( & root - > ordered_root ) ) ;
2016-06-23 01:54:23 +03:00
list_add_tail ( & root - > ordered_root , & fs_info - > ordered_roots ) ;
spin_unlock ( & fs_info - > ordered_root_lock ) ;
2013-05-15 11:48:23 +04:00
}
spin_unlock ( & root - > ordered_extent_lock ) ;
2008-07-24 19:57:52 +04:00
2017-10-19 21:15:55 +03:00
/*
* We don ' t need the count_max_extents here , we can assume that all of
* that work has been done at higher layers , so this is truly the
* smallest the extent is going to get .
*/
spin_lock ( & BTRFS_I ( inode ) - > lock ) ;
btrfs_mod_outstanding_extents ( BTRFS_I ( inode ) , 1 ) ;
spin_unlock ( & BTRFS_I ( inode ) - > lock ) ;
2008-01-08 23:46:30 +03:00
return 0 ;
}
2010-05-23 19:00:55 +04:00
int btrfs_add_ordered_extent ( struct inode * inode , u64 file_offset ,
2019-12-03 04:34:19 +03:00
u64 disk_bytenr , u64 num_bytes , u64 disk_num_bytes ,
int type )
2010-05-23 19:00:55 +04:00
{
2019-12-03 04:34:19 +03:00
return __btrfs_add_ordered_extent ( inode , file_offset , disk_bytenr ,
num_bytes , disk_num_bytes , type , 0 ,
2010-12-17 09:21:50 +03:00
BTRFS_COMPRESS_NONE ) ;
2010-05-23 19:00:55 +04:00
}
int btrfs_add_ordered_extent_dio ( struct inode * inode , u64 file_offset ,
2019-12-03 04:34:19 +03:00
u64 disk_bytenr , u64 num_bytes ,
u64 disk_num_bytes , int type )
2010-05-23 19:00:55 +04:00
{
2019-12-03 04:34:19 +03:00
return __btrfs_add_ordered_extent ( inode , file_offset , disk_bytenr ,
num_bytes , disk_num_bytes , type , 1 ,
2010-12-17 09:21:50 +03:00
BTRFS_COMPRESS_NONE ) ;
}
int btrfs_add_ordered_extent_compress ( struct inode * inode , u64 file_offset ,
2019-12-03 04:34:19 +03:00
u64 disk_bytenr , u64 num_bytes ,
u64 disk_num_bytes , int type ,
int compress_type )
2010-12-17 09:21:50 +03:00
{
2019-12-03 04:34:19 +03:00
return __btrfs_add_ordered_extent ( inode , file_offset , disk_bytenr ,
num_bytes , disk_num_bytes , type , 0 ,
2010-12-17 09:21:50 +03:00
compress_type ) ;
2010-05-23 19:00:55 +04:00
}
2008-07-17 21:53:27 +04:00
/*
* Add a struct btrfs_ordered_sum into the list of checksums to be inserted
2008-07-18 14:17:13 +04:00
* when an ordered extent is finished . If the list covers more than one
* ordered extent , it is split across multiples .
2008-07-17 21:53:27 +04:00
*/
2019-04-10 16:16:11 +03:00
void btrfs_add_ordered_sum ( struct btrfs_ordered_extent * entry ,
2012-03-01 17:56:26 +04:00
struct btrfs_ordered_sum * sum )
2008-01-08 23:46:30 +03:00
{
2008-07-17 20:53:50 +04:00
struct btrfs_ordered_inode_tree * tree ;
2008-01-08 23:46:30 +03:00
2019-04-10 16:16:11 +03:00
tree = & BTRFS_I ( entry - > inode ) - > ordered_tree ;
2012-05-02 22:00:54 +04:00
spin_lock_irq ( & tree - > lock ) ;
2008-07-17 20:53:50 +04:00
list_add_tail ( & sum - > list , & entry - > list ) ;
2012-05-02 22:00:54 +04:00
spin_unlock_irq ( & tree - > lock ) ;
2008-01-08 23:46:30 +03:00
}
2010-11-29 03:56:33 +03:00
/*
* this is used to account for finished IO across a given range
* of the file . The IO may span ordered extents . If
* a given ordered_extent is completely done , 1 is returned , otherwise
* 0.
*
* test_and_set_bit on a flag in the struct btrfs_ordered_extent is used
* to make sure this function only returns 1 once for a given ordered extent .
*
* file_offset is updated to one byte past the range that is recorded as
* complete . This allows you to walk forward in the file .
*/
int btrfs_dec_test_first_ordered_pending ( struct inode * inode ,
struct btrfs_ordered_extent * * cached ,
2012-05-02 22:00:54 +04:00
u64 * file_offset , u64 io_size , int uptodate )
2010-11-29 03:56:33 +03:00
{
2016-06-23 01:54:23 +03:00
struct btrfs_fs_info * fs_info = btrfs_sb ( inode - > i_sb ) ;
2010-11-29 03:56:33 +03:00
struct btrfs_ordered_inode_tree * tree ;
struct rb_node * node ;
struct btrfs_ordered_extent * entry = NULL ;
int ret ;
2012-05-02 22:00:54 +04:00
unsigned long flags ;
2010-11-29 03:56:33 +03:00
u64 dec_end ;
u64 dec_start ;
u64 to_dec ;
tree = & BTRFS_I ( inode ) - > ordered_tree ;
2012-05-02 22:00:54 +04:00
spin_lock_irqsave ( & tree - > lock , flags ) ;
2010-11-29 03:56:33 +03:00
node = tree_search ( tree , * file_offset ) ;
if ( ! node ) {
ret = 1 ;
goto out ;
}
entry = rb_entry ( node , struct btrfs_ordered_extent , rb_node ) ;
if ( ! offset_in_entry ( entry , * file_offset ) ) {
ret = 1 ;
goto out ;
}
dec_start = max ( * file_offset , entry - > file_offset ) ;
2019-12-03 04:34:19 +03:00
dec_end = min ( * file_offset + io_size ,
entry - > file_offset + entry - > num_bytes ) ;
2010-11-29 03:56:33 +03:00
* file_offset = dec_end ;
if ( dec_start > dec_end ) {
2016-06-23 01:54:23 +03:00
btrfs_crit ( fs_info , " bad ordering dec_start %llu end %llu " ,
dec_start , dec_end ) ;
2010-11-29 03:56:33 +03:00
}
to_dec = dec_end - dec_start ;
if ( to_dec > entry - > bytes_left ) {
2016-06-23 01:54:23 +03:00
btrfs_crit ( fs_info ,
" bad ordered accounting left %llu size %llu " ,
entry - > bytes_left , to_dec ) ;
2010-11-29 03:56:33 +03:00
}
entry - > bytes_left - = to_dec ;
2012-05-02 22:00:54 +04:00
if ( ! uptodate )
set_bit ( BTRFS_ORDERED_IOERR , & entry - > flags ) ;
2014-03-06 09:54:56 +04:00
if ( entry - > bytes_left = = 0 ) {
2010-11-29 03:56:33 +03:00
ret = test_and_set_bit ( BTRFS_ORDERED_IO_DONE , & entry - > flags ) ;
2018-02-26 18:15:17 +03:00
/* test_and_set_bit implies a barrier */
cond_wake_up_nomb ( & entry - > wait ) ;
2014-03-06 09:54:56 +04:00
} else {
2010-11-29 03:56:33 +03:00
ret = 1 ;
2014-03-06 09:54:56 +04:00
}
2010-11-29 03:56:33 +03:00
out :
if ( ! ret & & cached & & entry ) {
* cached = entry ;
2017-03-03 11:55:13 +03:00
refcount_inc ( & entry - > refs ) ;
2010-11-29 03:56:33 +03:00
}
2012-05-02 22:00:54 +04:00
spin_unlock_irqrestore ( & tree - > lock , flags ) ;
2010-11-29 03:56:33 +03:00
return ret = = 0 ;
}
2008-07-17 21:53:27 +04:00
/*
* this is used to account for finished IO across a given range
* of the file . The IO should not span ordered extents . If
* a given ordered_extent is completely done , 1 is returned , otherwise
* 0.
*
* test_and_set_bit on a flag in the struct btrfs_ordered_extent is used
* to make sure this function only returns 1 once for a given ordered extent .
*/
2008-07-17 20:53:50 +04:00
int btrfs_dec_test_ordered_pending ( struct inode * inode ,
2010-02-02 23:51:14 +03:00
struct btrfs_ordered_extent * * cached ,
2012-05-02 22:00:54 +04:00
u64 file_offset , u64 io_size , int uptodate )
2008-01-08 23:46:30 +03:00
{
2008-07-17 20:53:50 +04:00
struct btrfs_ordered_inode_tree * tree ;
2008-01-08 23:46:30 +03:00
struct rb_node * node ;
2010-02-02 23:51:14 +03:00
struct btrfs_ordered_extent * entry = NULL ;
2012-05-02 22:00:54 +04:00
unsigned long flags ;
2008-07-17 20:53:50 +04:00
int ret ;
tree = & BTRFS_I ( inode ) - > ordered_tree ;
2012-05-02 22:00:54 +04:00
spin_lock_irqsave ( & tree - > lock , flags ) ;
if ( cached & & * cached ) {
entry = * cached ;
goto have_entry ;
}
2008-07-17 20:53:50 +04:00
node = tree_search ( tree , file_offset ) ;
2008-01-08 23:46:30 +03:00
if ( ! node ) {
2008-07-17 20:53:50 +04:00
ret = 1 ;
goto out ;
2008-01-08 23:46:30 +03:00
}
2008-07-17 20:53:50 +04:00
entry = rb_entry ( node , struct btrfs_ordered_extent , rb_node ) ;
2012-05-02 22:00:54 +04:00
have_entry :
2008-07-17 20:53:50 +04:00
if ( ! offset_in_entry ( entry , file_offset ) ) {
ret = 1 ;
goto out ;
2008-01-08 23:46:30 +03:00
}
2008-07-17 20:53:50 +04:00
2009-09-03 00:53:46 +04:00
if ( io_size > entry - > bytes_left ) {
2013-12-20 20:37:06 +04:00
btrfs_crit ( BTRFS_I ( inode ) - > root - > fs_info ,
" bad ordered accounting left %llu size %llu " ,
2013-08-20 15:20:07 +04:00
entry - > bytes_left , io_size ) ;
2009-09-03 00:53:46 +04:00
}
entry - > bytes_left - = io_size ;
2012-05-02 22:00:54 +04:00
if ( ! uptodate )
set_bit ( BTRFS_ORDERED_IOERR , & entry - > flags ) ;
2014-03-06 09:54:56 +04:00
if ( entry - > bytes_left = = 0 ) {
2008-07-17 20:53:50 +04:00
ret = test_and_set_bit ( BTRFS_ORDERED_IO_DONE , & entry - > flags ) ;
2018-02-26 18:15:17 +03:00
/* test_and_set_bit implies a barrier */
cond_wake_up_nomb ( & entry - > wait ) ;
2014-03-06 09:54:56 +04:00
} else {
2009-09-03 00:53:46 +04:00
ret = 1 ;
2014-03-06 09:54:56 +04:00
}
2008-07-17 20:53:50 +04:00
out :
2010-02-02 23:51:14 +03:00
if ( ! ret & & cached & & entry ) {
* cached = entry ;
2017-03-03 11:55:13 +03:00
refcount_inc ( & entry - > refs ) ;
2010-02-02 23:51:14 +03:00
}
2012-05-02 22:00:54 +04:00
spin_unlock_irqrestore ( & tree - > lock , flags ) ;
2008-07-17 20:53:50 +04:00
return ret = = 0 ;
}
2008-01-08 23:46:30 +03:00
2008-07-17 21:53:27 +04:00
/*
* used to drop a reference on an ordered extent . This will free
* the extent if the last reference is dropped
*/
2012-03-01 17:56:26 +04:00
void btrfs_put_ordered_extent ( struct btrfs_ordered_extent * entry )
2008-07-17 20:53:50 +04:00
{
2008-07-17 20:54:15 +04:00
struct list_head * cur ;
struct btrfs_ordered_sum * sum ;
Btrfs: add initial tracepoint support for btrfs
Tracepoints can provide insight into why btrfs hits bugs and be greatly
helpful for debugging, e.g
dd-7822 [000] 2121.641088: btrfs_inode_request: root = 5(FS_TREE), gen = 4, ino = 256, blocks = 8, disk_i_size = 0, last_trans = 8, logged_trans = 0
dd-7822 [000] 2121.641100: btrfs_inode_new: root = 5(FS_TREE), gen = 8, ino = 257, blocks = 0, disk_i_size = 0, last_trans = 0, logged_trans = 0
btrfs-transacti-7804 [001] 2146.935420: btrfs_cow_block: root = 2(EXTENT_TREE), refs = 2, orig_buf = 29368320 (orig_level = 0), cow_buf = 29388800 (cow_level = 0)
btrfs-transacti-7804 [001] 2146.935473: btrfs_cow_block: root = 1(ROOT_TREE), refs = 2, orig_buf = 29364224 (orig_level = 0), cow_buf = 29392896 (cow_level = 0)
btrfs-transacti-7804 [001] 2146.972221: btrfs_transaction_commit: root = 1(ROOT_TREE), gen = 8
flush-btrfs-2-7821 [001] 2155.824210: btrfs_chunk_alloc: root = 3(CHUNK_TREE), offset = 1103101952, size = 1073741824, num_stripes = 1, sub_stripes = 0, type = DATA
flush-btrfs-2-7821 [001] 2155.824241: btrfs_cow_block: root = 2(EXTENT_TREE), refs = 2, orig_buf = 29388800 (orig_level = 0), cow_buf = 29396992 (cow_level = 0)
flush-btrfs-2-7821 [001] 2155.824255: btrfs_cow_block: root = 4(DEV_TREE), refs = 2, orig_buf = 29372416 (orig_level = 0), cow_buf = 29401088 (cow_level = 0)
flush-btrfs-2-7821 [000] 2155.824329: btrfs_cow_block: root = 3(CHUNK_TREE), refs = 2, orig_buf = 20971520 (orig_level = 0), cow_buf = 20975616 (cow_level = 0)
btrfs-endio-wri-7800 [001] 2155.898019: btrfs_cow_block: root = 5(FS_TREE), refs = 2, orig_buf = 29384704 (orig_level = 0), cow_buf = 29405184 (cow_level = 0)
btrfs-endio-wri-7800 [001] 2155.898043: btrfs_cow_block: root = 7(CSUM_TREE), refs = 2, orig_buf = 29376512 (orig_level = 0), cow_buf = 29409280 (cow_level = 0)
Here is what I have added:
1) ordere_extent:
btrfs_ordered_extent_add
btrfs_ordered_extent_remove
btrfs_ordered_extent_start
btrfs_ordered_extent_put
These provide critical information to understand how ordered_extents are
updated.
2) extent_map:
btrfs_get_extent
extent_map is used in both read and write cases, and it is useful for tracking
how btrfs specific IO is running.
3) writepage:
__extent_writepage
btrfs_writepage_end_io_hook
Pages are cirtical resourses and produce a lot of corner cases during writeback,
so it is valuable to know how page is written to disk.
4) inode:
btrfs_inode_new
btrfs_inode_request
btrfs_inode_evict
These can show where and when a inode is created, when a inode is evicted.
5) sync:
btrfs_sync_file
btrfs_sync_fs
These show sync arguments.
6) transaction:
btrfs_transaction_commit
In transaction based filesystem, it will be useful to know the generation and
who does commit.
7) back reference and cow:
btrfs_delayed_tree_ref
btrfs_delayed_data_ref
btrfs_delayed_ref_head
btrfs_cow_block
Btrfs natively supports back references, these tracepoints are helpful on
understanding btrfs's COW mechanism.
8) chunk:
btrfs_chunk_alloc
btrfs_chunk_free
Chunk is a link between physical offset and logical offset, and stands for space
infomation in btrfs, and these are helpful on tracing space things.
9) reserved_extent:
btrfs_reserved_extent_alloc
btrfs_reserved_extent_free
These can show how btrfs uses its space.
Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-03-24 14:18:59 +03:00
trace_btrfs_ordered_extent_put ( entry - > inode , entry ) ;
2017-03-03 11:55:13 +03:00
if ( refcount_dec_and_test ( & entry - > refs ) ) {
2015-07-01 14:13:10 +03:00
ASSERT ( list_empty ( & entry - > root_extent_list ) ) ;
ASSERT ( RB_EMPTY_NODE ( & entry - > rb_node ) ) ;
2012-05-02 22:00:54 +04:00
if ( entry - > inode )
btrfs_add_delayed_iput ( entry - > inode ) ;
2009-01-06 05:25:51 +03:00
while ( ! list_empty ( & entry - > list ) ) {
2008-07-17 20:54:15 +04:00
cur = entry - > list . next ;
sum = list_entry ( cur , struct btrfs_ordered_sum , list ) ;
list_del ( & sum - > list ) ;
2019-04-01 11:29:58 +03:00
kvfree ( sum ) ;
2008-07-17 20:54:15 +04:00
}
2012-09-06 14:01:51 +04:00
kmem_cache_free ( btrfs_ordered_extent_cache , entry ) ;
2008-07-17 20:54:15 +04:00
}
2008-01-08 23:46:30 +03:00
}
2008-01-15 16:40:48 +03:00
2008-07-17 21:53:27 +04:00
/*
* remove an ordered extent from the tree . No references are dropped
2012-05-02 22:00:54 +04:00
* and waiters are woken up .
2008-07-17 21:53:27 +04:00
*/
2012-05-02 22:00:54 +04:00
void btrfs_remove_ordered_extent ( struct inode * inode ,
struct btrfs_ordered_extent * entry )
2008-01-15 16:40:48 +03:00
{
2016-06-23 01:54:23 +03:00
struct btrfs_fs_info * fs_info = btrfs_sb ( inode - > i_sb ) ;
2008-07-17 20:53:50 +04:00
struct btrfs_ordered_inode_tree * tree ;
2017-10-19 21:15:55 +03:00
struct btrfs_inode * btrfs_inode = BTRFS_I ( inode ) ;
struct btrfs_root * root = btrfs_inode - > root ;
2008-01-15 16:40:48 +03:00
struct rb_node * node ;
2017-10-19 21:15:55 +03:00
/* This is paired with btrfs_add_ordered_extent. */
spin_lock ( & btrfs_inode - > lock ) ;
btrfs_mod_outstanding_extents ( btrfs_inode , - 1 ) ;
spin_unlock ( & btrfs_inode - > lock ) ;
if ( root ! = fs_info - > tree_root )
2019-12-03 04:34:19 +03:00
btrfs_delalloc_release_metadata ( btrfs_inode , entry - > num_bytes ,
false ) ;
2017-10-19 21:15:55 +03:00
2019-04-10 22:56:09 +03:00
if ( test_bit ( BTRFS_ORDERED_DIRECT , & entry - > flags ) )
2019-12-03 04:34:19 +03:00
percpu_counter_add_batch ( & fs_info - > dio_bytes , - entry - > num_bytes ,
2019-04-10 22:56:09 +03:00
fs_info - > delalloc_batch ) ;
2017-10-19 21:15:55 +03:00
tree = & btrfs_inode - > ordered_tree ;
2012-05-02 22:00:54 +04:00
spin_lock_irq ( & tree - > lock ) ;
2008-07-17 20:53:50 +04:00
node = & entry - > rb_node ;
2008-01-15 16:40:48 +03:00
rb_erase ( node , & tree - > tree ) ;
2015-07-01 14:13:10 +03:00
RB_CLEAR_NODE ( node ) ;
2013-11-22 22:54:58 +04:00
if ( tree - > last = = node )
tree - > last = NULL ;
2008-07-17 20:53:50 +04:00
set_bit ( BTRFS_ORDERED_COMPLETE , & entry - > flags ) ;
2012-05-02 22:00:54 +04:00
spin_unlock_irq ( & tree - > lock ) ;
2008-07-24 19:57:52 +04:00
2013-05-15 11:48:23 +04:00
spin_lock ( & root - > ordered_extent_lock ) ;
2008-07-24 19:57:52 +04:00
list_del_init ( & entry - > root_extent_list ) ;
2013-05-15 11:48:23 +04:00
root - > nr_ordered_extents - - ;
2009-03-31 21:27:11 +04:00
Btrfs: add initial tracepoint support for btrfs
Tracepoints can provide insight into why btrfs hits bugs and be greatly
helpful for debugging, e.g
dd-7822 [000] 2121.641088: btrfs_inode_request: root = 5(FS_TREE), gen = 4, ino = 256, blocks = 8, disk_i_size = 0, last_trans = 8, logged_trans = 0
dd-7822 [000] 2121.641100: btrfs_inode_new: root = 5(FS_TREE), gen = 8, ino = 257, blocks = 0, disk_i_size = 0, last_trans = 0, logged_trans = 0
btrfs-transacti-7804 [001] 2146.935420: btrfs_cow_block: root = 2(EXTENT_TREE), refs = 2, orig_buf = 29368320 (orig_level = 0), cow_buf = 29388800 (cow_level = 0)
btrfs-transacti-7804 [001] 2146.935473: btrfs_cow_block: root = 1(ROOT_TREE), refs = 2, orig_buf = 29364224 (orig_level = 0), cow_buf = 29392896 (cow_level = 0)
btrfs-transacti-7804 [001] 2146.972221: btrfs_transaction_commit: root = 1(ROOT_TREE), gen = 8
flush-btrfs-2-7821 [001] 2155.824210: btrfs_chunk_alloc: root = 3(CHUNK_TREE), offset = 1103101952, size = 1073741824, num_stripes = 1, sub_stripes = 0, type = DATA
flush-btrfs-2-7821 [001] 2155.824241: btrfs_cow_block: root = 2(EXTENT_TREE), refs = 2, orig_buf = 29388800 (orig_level = 0), cow_buf = 29396992 (cow_level = 0)
flush-btrfs-2-7821 [001] 2155.824255: btrfs_cow_block: root = 4(DEV_TREE), refs = 2, orig_buf = 29372416 (orig_level = 0), cow_buf = 29401088 (cow_level = 0)
flush-btrfs-2-7821 [000] 2155.824329: btrfs_cow_block: root = 3(CHUNK_TREE), refs = 2, orig_buf = 20971520 (orig_level = 0), cow_buf = 20975616 (cow_level = 0)
btrfs-endio-wri-7800 [001] 2155.898019: btrfs_cow_block: root = 5(FS_TREE), refs = 2, orig_buf = 29384704 (orig_level = 0), cow_buf = 29405184 (cow_level = 0)
btrfs-endio-wri-7800 [001] 2155.898043: btrfs_cow_block: root = 7(CSUM_TREE), refs = 2, orig_buf = 29376512 (orig_level = 0), cow_buf = 29409280 (cow_level = 0)
Here is what I have added:
1) ordere_extent:
btrfs_ordered_extent_add
btrfs_ordered_extent_remove
btrfs_ordered_extent_start
btrfs_ordered_extent_put
These provide critical information to understand how ordered_extents are
updated.
2) extent_map:
btrfs_get_extent
extent_map is used in both read and write cases, and it is useful for tracking
how btrfs specific IO is running.
3) writepage:
__extent_writepage
btrfs_writepage_end_io_hook
Pages are cirtical resourses and produce a lot of corner cases during writeback,
so it is valuable to know how page is written to disk.
4) inode:
btrfs_inode_new
btrfs_inode_request
btrfs_inode_evict
These can show where and when a inode is created, when a inode is evicted.
5) sync:
btrfs_sync_file
btrfs_sync_fs
These show sync arguments.
6) transaction:
btrfs_transaction_commit
In transaction based filesystem, it will be useful to know the generation and
who does commit.
7) back reference and cow:
btrfs_delayed_tree_ref
btrfs_delayed_data_ref
btrfs_delayed_ref_head
btrfs_cow_block
Btrfs natively supports back references, these tracepoints are helpful on
understanding btrfs's COW mechanism.
8) chunk:
btrfs_chunk_alloc
btrfs_chunk_free
Chunk is a link between physical offset and logical offset, and stands for space
infomation in btrfs, and these are helpful on tracing space things.
9) reserved_extent:
btrfs_reserved_extent_alloc
btrfs_reserved_extent_free
These can show how btrfs uses its space.
Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-03-24 14:18:59 +03:00
trace_btrfs_ordered_extent_remove ( inode , entry ) ;
2013-05-15 11:48:23 +04:00
if ( ! root - > nr_ordered_extents ) {
2016-06-23 01:54:23 +03:00
spin_lock ( & fs_info - > ordered_root_lock ) ;
2013-05-15 11:48:23 +04:00
BUG_ON ( list_empty ( & root - > ordered_root ) ) ;
list_del_init ( & root - > ordered_root ) ;
2016-06-23 01:54:23 +03:00
spin_unlock ( & fs_info - > ordered_root_lock ) ;
2013-05-15 11:48:23 +04:00
}
spin_unlock ( & root - > ordered_extent_lock ) ;
2008-07-17 20:53:50 +04:00
wake_up ( & entry - > wait ) ;
2008-01-15 16:40:48 +03:00
}
2014-02-28 06:46:19 +04:00
static void btrfs_run_ordered_extent_work ( struct btrfs_work * work )
2012-10-25 13:41:36 +04:00
{
struct btrfs_ordered_extent * ordered ;
ordered = container_of ( work , struct btrfs_ordered_extent , flush_work ) ;
btrfs_start_ordered_extent ( ordered - > inode , ordered , 1 ) ;
complete ( & ordered - > completion ) ;
}
2008-09-29 23:18:18 +04:00
/*
* wait for all the ordered extents in a root . This is done when balancing
* space between drives .
*/
2017-06-23 19:48:21 +03:00
u64 btrfs_wait_ordered_extents ( struct btrfs_root * root , u64 nr ,
2016-04-26 17:36:38 +03:00
const u64 range_start , const u64 range_len )
2008-07-24 19:57:52 +04:00
{
2016-06-23 01:54:23 +03:00
struct btrfs_fs_info * fs_info = root - > fs_info ;
2016-04-26 17:36:38 +03:00
LIST_HEAD ( splice ) ;
LIST_HEAD ( skipped ) ;
LIST_HEAD ( works ) ;
2012-10-25 13:41:36 +04:00
struct btrfs_ordered_extent * ordered , * next ;
2017-06-23 19:48:21 +03:00
u64 count = 0 ;
2016-04-26 17:36:38 +03:00
const u64 range_end = range_start + range_len ;
2008-07-24 19:57:52 +04:00
2014-03-06 09:55:02 +04:00
mutex_lock ( & root - > ordered_extent_mutex ) ;
2013-05-15 11:48:23 +04:00
spin_lock ( & root - > ordered_extent_lock ) ;
list_splice_init ( & root - > ordered_extents , & splice ) ;
2013-11-04 19:13:25 +04:00
while ( ! list_empty ( & splice ) & & nr ) {
2013-05-15 11:48:23 +04:00
ordered = list_first_entry ( & splice , struct btrfs_ordered_extent ,
root_extent_list ) ;
2016-04-26 17:36:38 +03:00
2019-12-03 04:34:19 +03:00
if ( range_end < = ordered - > disk_bytenr | |
ordered - > disk_bytenr + ordered - > disk_num_bytes < = range_start ) {
2016-04-26 17:36:38 +03:00
list_move_tail ( & ordered - > root_extent_list , & skipped ) ;
cond_resched_lock ( & root - > ordered_extent_lock ) ;
continue ;
}
2013-05-15 11:48:23 +04:00
list_move_tail ( & ordered - > root_extent_list ,
& root - > ordered_extents ) ;
2017-03-03 11:55:13 +03:00
refcount_inc ( & ordered - > refs ) ;
2013-05-15 11:48:23 +04:00
spin_unlock ( & root - > ordered_extent_lock ) ;
2008-07-24 19:57:52 +04:00
2014-02-28 06:46:09 +04:00
btrfs_init_work ( & ordered - > flush_work ,
btrfs_run_ordered_extent_work , NULL , NULL ) ;
2013-05-15 11:48:23 +04:00
list_add_tail ( & ordered - > work_list , & works ) ;
2016-06-23 01:54:23 +03:00
btrfs_queue_work ( fs_info - > flush_workers , & ordered - > flush_work ) ;
2008-07-24 19:57:52 +04:00
2012-10-25 13:41:36 +04:00
cond_resched ( ) ;
2013-05-15 11:48:23 +04:00
spin_lock ( & root - > ordered_extent_lock ) ;
2017-06-23 19:48:21 +03:00
if ( nr ! = U64_MAX )
2013-11-04 19:13:25 +04:00
nr - - ;
count + + ;
2008-07-24 19:57:52 +04:00
}
2016-04-26 17:36:38 +03:00
list_splice_tail ( & skipped , & root - > ordered_extents ) ;
2013-11-04 19:13:25 +04:00
list_splice_tail ( & splice , & root - > ordered_extents ) ;
2013-05-15 11:48:23 +04:00
spin_unlock ( & root - > ordered_extent_lock ) ;
2012-10-25 13:41:36 +04:00
list_for_each_entry_safe ( ordered , next , & works , work_list ) {
list_del_init ( & ordered - > work_list ) ;
wait_for_completion ( & ordered - > completion ) ;
btrfs_put_ordered_extent ( ordered ) ;
cond_resched ( ) ;
}
2014-03-06 09:55:02 +04:00
mutex_unlock ( & root - > ordered_extent_mutex ) ;
2013-11-04 19:13:25 +04:00
return count ;
2008-07-24 19:57:52 +04:00
}
Btrfs: fix block group remaining RO forever after error during device replace
When doing a device replace, while at scrub.c:scrub_enumerate_chunks(), we
set the block group to RO mode and then wait for any ongoing writes into
extents of the block group to complete. While doing that wait we overwrite
the value of the variable 'ret' and can break out of the loop if an error
happens without turning the block group back into RW mode. So what happens
is the following:
1) btrfs_inc_block_group_ro() returns 0, meaning it set the block group
to RO mode (its ->ro field set to 1 or incremented to some value > 1);
2) Then btrfs_wait_ordered_roots() returns a value > 0;
3) Then if either joining or committing the transaction fails, we break
out of the loop wihtout calling btrfs_dec_block_group_ro(), leaving
the block group in RO mode forever.
To fix this, just remove the code that waits for ongoing writes to extents
of the block group, since it's not needed because in the initial setup
phase of a device replace operation, before starting to find all chunks
and their extents, we set the target device for replace while holding
fs_info->dev_replace->rwsem, which ensures that after releasing that
semaphore, any writes into the source device are made to the target device
as well (__btrfs_map_block() guarantees that). So while at
scrub_enumerate_chunks() we only need to worry about finding and copying
extents (from the source device to the target device) that were written
before we started the device replace operation.
Fixes: f0e9b7d6401959 ("Btrfs: fix race setting block group readonly during device replace")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2019-11-14 21:02:43 +03:00
void btrfs_wait_ordered_roots ( struct btrfs_fs_info * fs_info , u64 nr ,
2017-06-23 19:48:21 +03:00
const u64 range_start , const u64 range_len )
2013-05-15 11:48:23 +04:00
{
struct btrfs_root * root ;
struct list_head splice ;
2017-06-23 19:48:21 +03:00
u64 done ;
2013-05-15 11:48:23 +04:00
INIT_LIST_HEAD ( & splice ) ;
2014-03-06 09:54:55 +04:00
mutex_lock ( & fs_info - > ordered_operations_mutex ) ;
2013-05-15 11:48:23 +04:00
spin_lock ( & fs_info - > ordered_root_lock ) ;
list_splice_init ( & fs_info - > ordered_roots , & splice ) ;
2013-11-04 19:13:25 +04:00
while ( ! list_empty ( & splice ) & & nr ) {
2013-05-15 11:48:23 +04:00
root = list_first_entry ( & splice , struct btrfs_root ,
ordered_root ) ;
2020-01-24 17:33:01 +03:00
root = btrfs_grab_root ( root ) ;
2013-05-15 11:48:23 +04:00
BUG_ON ( ! root ) ;
list_move_tail ( & root - > ordered_root ,
& fs_info - > ordered_roots ) ;
spin_unlock ( & fs_info - > ordered_root_lock ) ;
2016-04-26 17:36:38 +03:00
done = btrfs_wait_ordered_extents ( root , nr ,
range_start , range_len ) ;
2020-01-24 17:33:01 +03:00
btrfs_put_root ( root ) ;
2013-05-15 11:48:23 +04:00
spin_lock ( & fs_info - > ordered_root_lock ) ;
2017-06-23 19:48:21 +03:00
if ( nr ! = U64_MAX ) {
2013-11-04 19:13:25 +04:00
nr - = done ;
}
2013-05-15 11:48:23 +04:00
}
2013-11-14 13:33:21 +04:00
list_splice_tail ( & splice , & fs_info - > ordered_roots ) ;
2013-05-15 11:48:23 +04:00
spin_unlock ( & fs_info - > ordered_root_lock ) ;
2014-03-06 09:54:55 +04:00
mutex_unlock ( & fs_info - > ordered_operations_mutex ) ;
2013-05-15 11:48:23 +04:00
}
2008-07-17 21:53:27 +04:00
/*
* Used to start IO or wait for a given ordered extent to finish .
*
* If wait is one , this effectively waits on page writeback for all the pages
* in the extent , and it waits on the io completion code to insert
* metadata into the btree corresponding to the extent
*/
void btrfs_start_ordered_extent ( struct inode * inode ,
struct btrfs_ordered_extent * entry ,
int wait )
2008-07-17 20:53:50 +04:00
{
u64 start = entry - > file_offset ;
2019-12-03 04:34:19 +03:00
u64 end = start + entry - > num_bytes - 1 ;
2008-05-27 18:55:43 +04:00
Btrfs: add initial tracepoint support for btrfs
Tracepoints can provide insight into why btrfs hits bugs and be greatly
helpful for debugging, e.g
dd-7822 [000] 2121.641088: btrfs_inode_request: root = 5(FS_TREE), gen = 4, ino = 256, blocks = 8, disk_i_size = 0, last_trans = 8, logged_trans = 0
dd-7822 [000] 2121.641100: btrfs_inode_new: root = 5(FS_TREE), gen = 8, ino = 257, blocks = 0, disk_i_size = 0, last_trans = 0, logged_trans = 0
btrfs-transacti-7804 [001] 2146.935420: btrfs_cow_block: root = 2(EXTENT_TREE), refs = 2, orig_buf = 29368320 (orig_level = 0), cow_buf = 29388800 (cow_level = 0)
btrfs-transacti-7804 [001] 2146.935473: btrfs_cow_block: root = 1(ROOT_TREE), refs = 2, orig_buf = 29364224 (orig_level = 0), cow_buf = 29392896 (cow_level = 0)
btrfs-transacti-7804 [001] 2146.972221: btrfs_transaction_commit: root = 1(ROOT_TREE), gen = 8
flush-btrfs-2-7821 [001] 2155.824210: btrfs_chunk_alloc: root = 3(CHUNK_TREE), offset = 1103101952, size = 1073741824, num_stripes = 1, sub_stripes = 0, type = DATA
flush-btrfs-2-7821 [001] 2155.824241: btrfs_cow_block: root = 2(EXTENT_TREE), refs = 2, orig_buf = 29388800 (orig_level = 0), cow_buf = 29396992 (cow_level = 0)
flush-btrfs-2-7821 [001] 2155.824255: btrfs_cow_block: root = 4(DEV_TREE), refs = 2, orig_buf = 29372416 (orig_level = 0), cow_buf = 29401088 (cow_level = 0)
flush-btrfs-2-7821 [000] 2155.824329: btrfs_cow_block: root = 3(CHUNK_TREE), refs = 2, orig_buf = 20971520 (orig_level = 0), cow_buf = 20975616 (cow_level = 0)
btrfs-endio-wri-7800 [001] 2155.898019: btrfs_cow_block: root = 5(FS_TREE), refs = 2, orig_buf = 29384704 (orig_level = 0), cow_buf = 29405184 (cow_level = 0)
btrfs-endio-wri-7800 [001] 2155.898043: btrfs_cow_block: root = 7(CSUM_TREE), refs = 2, orig_buf = 29376512 (orig_level = 0), cow_buf = 29409280 (cow_level = 0)
Here is what I have added:
1) ordere_extent:
btrfs_ordered_extent_add
btrfs_ordered_extent_remove
btrfs_ordered_extent_start
btrfs_ordered_extent_put
These provide critical information to understand how ordered_extents are
updated.
2) extent_map:
btrfs_get_extent
extent_map is used in both read and write cases, and it is useful for tracking
how btrfs specific IO is running.
3) writepage:
__extent_writepage
btrfs_writepage_end_io_hook
Pages are cirtical resourses and produce a lot of corner cases during writeback,
so it is valuable to know how page is written to disk.
4) inode:
btrfs_inode_new
btrfs_inode_request
btrfs_inode_evict
These can show where and when a inode is created, when a inode is evicted.
5) sync:
btrfs_sync_file
btrfs_sync_fs
These show sync arguments.
6) transaction:
btrfs_transaction_commit
In transaction based filesystem, it will be useful to know the generation and
who does commit.
7) back reference and cow:
btrfs_delayed_tree_ref
btrfs_delayed_data_ref
btrfs_delayed_ref_head
btrfs_cow_block
Btrfs natively supports back references, these tracepoints are helpful on
understanding btrfs's COW mechanism.
8) chunk:
btrfs_chunk_alloc
btrfs_chunk_free
Chunk is a link between physical offset and logical offset, and stands for space
infomation in btrfs, and these are helpful on tracing space things.
9) reserved_extent:
btrfs_reserved_extent_alloc
btrfs_reserved_extent_free
These can show how btrfs uses its space.
Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-03-24 14:18:59 +03:00
trace_btrfs_ordered_extent_start ( inode , entry ) ;
2008-07-17 21:53:27 +04:00
/*
* pages in the range can be dirty , clean or writeback . We
* start IO on any dirty ones so the wait doesn ' t stall waiting
2012-07-25 19:12:06 +04:00
* for the flusher thread to find them
2008-07-17 21:53:27 +04:00
*/
2010-05-23 19:00:55 +04:00
if ( ! test_bit ( BTRFS_ORDERED_DIRECT , & entry - > flags ) )
filemap_fdatawrite_range ( inode - > i_mapping , start , end ) ;
Btrfs: Add zlib compression support
This is a large change for adding compression on reading and writing,
both for inline and regular extents. It does some fairly large
surgery to the writeback paths.
Compression is off by default and enabled by mount -o compress. Even
when the -o compress mount option is not used, it is possible to read
compressed extents off the disk.
If compression for a given set of pages fails to make them smaller, the
file is flagged to avoid future compression attempts later.
* While finding delalloc extents, the pages are locked before being sent down
to the delalloc handler. This allows the delalloc handler to do complex things
such as cleaning the pages, marking them writeback and starting IO on their
behalf.
* Inline extents are inserted at delalloc time now. This allows us to compress
the data before inserting the inline extent, and it allows us to insert
an inline extent that spans multiple pages.
* All of the in-memory extent representations (extent_map.c, ordered-data.c etc)
are changed to record both an in-memory size and an on disk size, as well
as a flag for compression.
From a disk format point of view, the extent pointers in the file are changed
to record the on disk size of a given extent and some encoding flags.
Space in the disk format is allocated for compression encoding, as well
as encryption and a generic 'other' field. Neither the encryption or the
'other' field are currently used.
In order to limit the amount of data read for a single random read in the
file, the size of a compressed extent is limited to 128k. This is a
software only limit, the disk format supports u64 sized compressed extents.
In order to limit the ram consumed while processing extents, the uncompressed
size of a compressed extent is limited to 256k. This is a software only limit
and will be subject to tuning later.
Checksumming is still done on compressed extents, and it is done on the
uncompressed version of the data. This way additional encodings can be
layered on without having to figure out which encoding to checksum.
Compression happens at delalloc time, which is basically singled threaded because
it is usually done by a single pdflush thread. This makes it tricky to
spread the compression load across all the cpus on the box. We'll have to
look at parallel pdflush walks of dirty inodes at a later time.
Decompression is hooked into readpages and it does spread across CPUs nicely.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-10-29 21:49:59 +03:00
if ( wait ) {
2008-07-17 20:53:50 +04:00
wait_event ( entry - > wait , test_bit ( BTRFS_ORDERED_COMPLETE ,
& entry - > flags ) ) ;
Btrfs: Add zlib compression support
This is a large change for adding compression on reading and writing,
both for inline and regular extents. It does some fairly large
surgery to the writeback paths.
Compression is off by default and enabled by mount -o compress. Even
when the -o compress mount option is not used, it is possible to read
compressed extents off the disk.
If compression for a given set of pages fails to make them smaller, the
file is flagged to avoid future compression attempts later.
* While finding delalloc extents, the pages are locked before being sent down
to the delalloc handler. This allows the delalloc handler to do complex things
such as cleaning the pages, marking them writeback and starting IO on their
behalf.
* Inline extents are inserted at delalloc time now. This allows us to compress
the data before inserting the inline extent, and it allows us to insert
an inline extent that spans multiple pages.
* All of the in-memory extent representations (extent_map.c, ordered-data.c etc)
are changed to record both an in-memory size and an on disk size, as well
as a flag for compression.
From a disk format point of view, the extent pointers in the file are changed
to record the on disk size of a given extent and some encoding flags.
Space in the disk format is allocated for compression encoding, as well
as encryption and a generic 'other' field. Neither the encryption or the
'other' field are currently used.
In order to limit the amount of data read for a single random read in the
file, the size of a compressed extent is limited to 128k. This is a
software only limit, the disk format supports u64 sized compressed extents.
In order to limit the ram consumed while processing extents, the uncompressed
size of a compressed extent is limited to 256k. This is a software only limit
and will be subject to tuning later.
Checksumming is still done on compressed extents, and it is done on the
uncompressed version of the data. This way additional encodings can be
layered on without having to figure out which encoding to checksum.
Compression happens at delalloc time, which is basically singled threaded because
it is usually done by a single pdflush thread. This makes it tricky to
spread the compression load across all the cpus on the box. We'll have to
look at parallel pdflush walks of dirty inodes at a later time.
Decompression is hooked into readpages and it does spread across CPUs nicely.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-10-29 21:49:59 +03:00
}
2008-07-17 20:53:50 +04:00
}
2008-01-15 16:40:48 +03:00
2008-07-17 21:53:27 +04:00
/*
* Used to wait on ordered extents across a large range of bytes .
*/
2013-10-26 00:13:35 +04:00
int btrfs_wait_ordered_range ( struct inode * inode , u64 start , u64 len )
2008-07-17 20:53:50 +04:00
{
2013-10-26 00:13:35 +04:00
int ret = 0 ;
2015-05-05 21:03:10 +03:00
int ret_wb = 0 ;
2008-07-17 20:53:50 +04:00
u64 end ;
2008-07-19 04:42:20 +04:00
u64 orig_end ;
2008-07-17 20:53:50 +04:00
struct btrfs_ordered_extent * ordered ;
2008-07-19 04:42:20 +04:00
if ( start + len < start ) {
2008-07-22 19:18:09 +04:00
orig_end = INT_LIMIT ( loff_t ) ;
2008-07-19 04:42:20 +04:00
} else {
orig_end = start + len - 1 ;
2008-07-22 19:18:09 +04:00
if ( orig_end > INT_LIMIT ( loff_t ) )
orig_end = INT_LIMIT ( loff_t ) ;
2008-07-19 04:42:20 +04:00
}
2012-04-23 22:41:09 +04:00
2008-07-19 04:42:20 +04:00
/* start IO across the range first to instantiate any delalloc
* extents
*/
2014-10-10 12:43:11 +04:00
ret = btrfs_fdatawrite_range ( inode , start , orig_end ) ;
2013-10-26 00:13:35 +04:00
if ( ret )
return ret ;
2014-10-10 12:43:11 +04:00
2015-05-05 21:03:10 +03:00
/*
* If we have a writeback error don ' t return immediately . Wait first
* for any ordered extents that haven ' t completed yet . This is to make
* sure no one can dirty the same page ranges and call writepages ( )
* before the ordered extents complete - to avoid failures ( - EEXIST )
* when adding the new ordered extents to the ordered tree .
*/
ret_wb = filemap_fdatawait_range ( inode - > i_mapping , start , orig_end ) ;
2008-07-19 04:42:20 +04:00
2008-07-22 19:18:09 +04:00
end = orig_end ;
2009-01-06 05:25:51 +03:00
while ( 1 ) {
2008-07-17 20:53:50 +04:00
ordered = btrfs_lookup_first_ordered_extent ( inode , end ) ;
2009-01-06 05:25:51 +03:00
if ( ! ordered )
2008-07-17 20:53:50 +04:00
break ;
2008-07-19 04:42:20 +04:00
if ( ordered - > file_offset > orig_end ) {
2008-07-17 20:53:50 +04:00
btrfs_put_ordered_extent ( ordered ) ;
break ;
}
2019-12-03 04:34:19 +03:00
if ( ordered - > file_offset + ordered - > num_bytes < = start ) {
2008-07-17 20:53:50 +04:00
btrfs_put_ordered_extent ( ordered ) ;
break ;
}
2008-07-19 04:42:20 +04:00
btrfs_start_ordered_extent ( inode , ordered , 1 ) ;
2008-07-17 20:53:50 +04:00
end = ordered - > file_offset ;
2020-02-13 15:29:50 +03:00
/*
* If the ordered extent had an error save the error but don ' t
* exit without waiting first for all other ordered extents in
* the range to complete .
*/
2013-10-26 00:13:35 +04:00
if ( test_bit ( BTRFS_ORDERED_IOERR , & ordered - > flags ) )
ret = - EIO ;
2008-07-17 20:53:50 +04:00
btrfs_put_ordered_extent ( ordered ) ;
2020-02-13 15:29:50 +03:00
if ( end = = 0 | | end = = start )
2008-07-17 20:53:50 +04:00
break ;
end - - ;
}
2015-05-05 21:03:10 +03:00
return ret_wb ? ret_wb : ret ;
2008-01-15 16:40:48 +03:00
}
2008-07-17 21:53:27 +04:00
/*
* find an ordered extent corresponding to file_offset . return NULL if
* nothing is found , otherwise take a reference on the extent and return it
*/
2008-07-17 20:53:50 +04:00
struct btrfs_ordered_extent * btrfs_lookup_ordered_extent ( struct inode * inode ,
u64 file_offset )
{
struct btrfs_ordered_inode_tree * tree ;
struct rb_node * node ;
struct btrfs_ordered_extent * entry = NULL ;
tree = & BTRFS_I ( inode ) - > ordered_tree ;
2012-05-02 22:00:54 +04:00
spin_lock_irq ( & tree - > lock ) ;
2008-07-17 20:53:50 +04:00
node = tree_search ( tree , file_offset ) ;
if ( ! node )
goto out ;
entry = rb_entry ( node , struct btrfs_ordered_extent , rb_node ) ;
if ( ! offset_in_entry ( entry , file_offset ) )
entry = NULL ;
if ( entry )
2017-03-03 11:55:13 +03:00
refcount_inc ( & entry - > refs ) ;
2008-07-17 20:53:50 +04:00
out :
2012-05-02 22:00:54 +04:00
spin_unlock_irq ( & tree - > lock ) ;
2008-07-17 20:53:50 +04:00
return entry ;
}
2010-05-23 19:00:55 +04:00
/* Since the DIO code tries to lock a wide area we need to look for any ordered
* extents that exist in the range , rather than just the start of the range .
*/
2017-02-20 14:50:49 +03:00
struct btrfs_ordered_extent * btrfs_lookup_ordered_range (
struct btrfs_inode * inode , u64 file_offset , u64 len )
2010-05-23 19:00:55 +04:00
{
struct btrfs_ordered_inode_tree * tree ;
struct rb_node * node ;
struct btrfs_ordered_extent * entry = NULL ;
2017-02-20 14:50:49 +03:00
tree = & inode - > ordered_tree ;
2012-05-02 22:00:54 +04:00
spin_lock_irq ( & tree - > lock ) ;
2010-05-23 19:00:55 +04:00
node = tree_search ( tree , file_offset ) ;
if ( ! node ) {
node = tree_search ( tree , file_offset + len ) ;
if ( ! node )
goto out ;
}
while ( 1 ) {
entry = rb_entry ( node , struct btrfs_ordered_extent , rb_node ) ;
if ( range_overlaps ( entry , file_offset , len ) )
break ;
if ( entry - > file_offset > = file_offset + len ) {
entry = NULL ;
break ;
}
entry = NULL ;
node = rb_next ( node ) ;
if ( ! node )
break ;
}
out :
if ( entry )
2017-03-03 11:55:13 +03:00
refcount_inc ( & entry - > refs ) ;
2012-05-02 22:00:54 +04:00
spin_unlock_irq ( & tree - > lock ) ;
2010-05-23 19:00:55 +04:00
return entry ;
}
2008-07-17 21:53:27 +04:00
/*
* lookup and return any extent before ' file_offset ' . NULL is returned
* if none is found
*/
2008-07-17 20:53:50 +04:00
struct btrfs_ordered_extent *
2009-01-06 05:25:51 +03:00
btrfs_lookup_first_ordered_extent ( struct inode * inode , u64 file_offset )
2008-07-17 20:53:50 +04:00
{
struct btrfs_ordered_inode_tree * tree ;
struct rb_node * node ;
struct btrfs_ordered_extent * entry = NULL ;
tree = & BTRFS_I ( inode ) - > ordered_tree ;
2012-05-02 22:00:54 +04:00
spin_lock_irq ( & tree - > lock ) ;
2008-07-17 20:53:50 +04:00
node = tree_search ( tree , file_offset ) ;
if ( ! node )
goto out ;
entry = rb_entry ( node , struct btrfs_ordered_extent , rb_node ) ;
2017-03-03 11:55:13 +03:00
refcount_inc ( & entry - > refs ) ;
2008-07-17 20:53:50 +04:00
out :
2012-05-02 22:00:54 +04:00
spin_unlock_irq ( & tree - > lock ) ;
2008-07-17 20:53:50 +04:00
return entry ;
2008-04-25 16:51:48 +04:00
}
2008-07-17 20:54:05 +04:00
2008-07-17 21:53:27 +04:00
/*
* search the ordered extents for one corresponding to ' offset ' and
* try to find a checksum . This is used because we allow pages to
* be reclaimed before their checksum is actually put into the btree
*/
Btrfs: move data checksumming into a dedicated tree
Btrfs stores checksums for each data block. Until now, they have
been stored in the subvolume trees, indexed by the inode that is
referencing the data block. This means that when we read the inode,
we've probably read in at least some checksums as well.
But, this has a few problems:
* The checksums are indexed by logical offset in the file. When
compression is on, this means we have to do the expensive checksumming
on the uncompressed data. It would be faster if we could checksum
the compressed data instead.
* If we implement encryption, we'll be checksumming the plain text and
storing that on disk. This is significantly less secure.
* For either compression or encryption, we have to get the plain text
back before we can verify the checksum as correct. This makes the raid
layer balancing and extent moving much more expensive.
* It makes the front end caching code more complex, as we have touch
the subvolume and inodes as we cache extents.
* There is potentitally one copy of the checksum in each subvolume
referencing an extent.
The solution used here is to store the extent checksums in a dedicated
tree. This allows us to index the checksums by phyiscal extent
start and length. It means:
* The checksum is against the data stored on disk, after any compression
or encryption is done.
* The checksum is stored in a central location, and can be verified without
following back references, or reading inodes.
This makes compression significantly faster by reducing the amount of
data that needs to be checksummed. It will also allow much faster
raid management code in general.
The checksums are indexed by a key with a fixed objectid (a magic value
in ctree.h) and offset set to the starting byte of the extent. This
allows us to copy the checksum items into the fsync log tree directly (or
any other tree), without having to invent a second format for them.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-12-09 00:58:54 +03:00
int btrfs_find_ordered_sum ( struct inode * inode , u64 offset , u64 disk_bytenr ,
2019-05-22 11:19:01 +03:00
u8 * sum , int len )
2008-07-17 20:54:15 +04:00
{
2019-05-22 11:19:01 +03:00
struct btrfs_fs_info * fs_info = btrfs_sb ( inode - > i_sb ) ;
2008-07-17 20:54:15 +04:00
struct btrfs_ordered_sum * ordered_sum ;
struct btrfs_ordered_extent * ordered ;
struct btrfs_ordered_inode_tree * tree = & BTRFS_I ( inode ) - > ordered_tree ;
2008-07-18 14:17:13 +04:00
unsigned long num_sectors ;
unsigned long i ;
2016-06-15 16:22:56 +03:00
u32 sectorsize = btrfs_inode_sectorsize ( inode ) ;
2019-05-22 11:19:01 +03:00
const u16 csum_size = btrfs_super_csum_size ( fs_info - > super_copy ) ;
2013-04-05 11:20:56 +04:00
int index = 0 ;
2008-07-17 20:54:15 +04:00
ordered = btrfs_lookup_ordered_extent ( inode , offset ) ;
if ( ! ordered )
2013-04-05 11:20:56 +04:00
return 0 ;
2008-07-17 20:54:15 +04:00
2012-05-02 22:00:54 +04:00
spin_lock_irq ( & tree - > lock ) ;
2009-01-21 18:59:08 +03:00
list_for_each_entry_reverse ( ordered_sum , & ordered - > list , list ) {
2013-04-05 11:20:56 +04:00
if ( disk_bytenr > = ordered_sum - > bytenr & &
disk_bytenr < ordered_sum - > bytenr + ordered_sum - > len ) {
i = ( disk_bytenr - ordered_sum - > bytenr ) > >
inode - > i_sb - > s_blocksize_bits ;
num_sectors = ordered_sum - > len > >
inode - > i_sb - > s_blocksize_bits ;
Btrfs: remove btrfs_sector_sum structure
Using the structure btrfs_sector_sum to keep the checksum value is
unnecessary, because the extents that btrfs_sector_sum points to are
continuous, we can find out the expected checksums by btrfs_ordered_sum's
bytenr and the offset, so we can remove btrfs_sector_sum's bytenr. After
removing bytenr, there is only one member in the structure, so it makes
no sense to keep the structure, just remove it, and use a u32 array to
store the checksum value.
By this change, we don't use the while loop to get the checksums one by
one. Now, we can get several checksum value at one time, it improved the
performance by ~74% on my SSD (31MB/s -> 54MB/s).
test command:
# dd if=/dev/zero of=/mnt/btrfs/file0 bs=1M count=1024 oflag=sync
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-06-19 06:36:09 +04:00
num_sectors = min_t ( int , len - index , num_sectors - i ) ;
2019-05-22 11:19:01 +03:00
memcpy ( sum + index , ordered_sum - > sums + i * csum_size ,
num_sectors * csum_size ) ;
Btrfs: remove btrfs_sector_sum structure
Using the structure btrfs_sector_sum to keep the checksum value is
unnecessary, because the extents that btrfs_sector_sum points to are
continuous, we can find out the expected checksums by btrfs_ordered_sum's
bytenr and the offset, so we can remove btrfs_sector_sum's bytenr. After
removing bytenr, there is only one member in the structure, so it makes
no sense to keep the structure, just remove it, and use a u32 array to
store the checksum value.
By this change, we don't use the while loop to get the checksums one by
one. Now, we can get several checksum value at one time, it improved the
performance by ~74% on my SSD (31MB/s -> 54MB/s).
test command:
# dd if=/dev/zero of=/mnt/btrfs/file0 bs=1M count=1024 oflag=sync
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-06-19 06:36:09 +04:00
2019-05-22 11:19:01 +03:00
index + = ( int ) num_sectors * csum_size ;
Btrfs: remove btrfs_sector_sum structure
Using the structure btrfs_sector_sum to keep the checksum value is
unnecessary, because the extents that btrfs_sector_sum points to are
continuous, we can find out the expected checksums by btrfs_ordered_sum's
bytenr and the offset, so we can remove btrfs_sector_sum's bytenr. After
removing bytenr, there is only one member in the structure, so it makes
no sense to keep the structure, just remove it, and use a u32 array to
store the checksum value.
By this change, we don't use the while loop to get the checksums one by
one. Now, we can get several checksum value at one time, it improved the
performance by ~74% on my SSD (31MB/s -> 54MB/s).
test command:
# dd if=/dev/zero of=/mnt/btrfs/file0 bs=1M count=1024 oflag=sync
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-06-19 06:36:09 +04:00
if ( index = = len )
goto out ;
disk_bytenr + = num_sectors * sectorsize ;
2008-07-17 20:54:15 +04:00
}
}
out :
2012-05-02 22:00:54 +04:00
spin_unlock_irq ( & tree - > lock ) ;
2008-07-24 17:41:53 +04:00
btrfs_put_ordered_extent ( ordered ) ;
2013-04-05 11:20:56 +04:00
return index ;
2008-07-17 20:54:15 +04:00
}
2019-05-07 10:19:22 +03:00
/*
* btrfs_flush_ordered_range - Lock the passed range and ensures all pending
* ordered extents in it are run to completion .
*
* @ inode : Inode whose ordered tree is to be searched
* @ start : Beginning of range to flush
* @ end : Last byte of range to lock
* @ cached_state : If passed , will return the extent state responsible for the
* locked range . It ' s the caller ' s responsibility to free the cached state .
*
* This function always returns with the given range locked , ensuring after it ' s
* called no order extent can be pending .
*/
2020-02-05 21:09:33 +03:00
void btrfs_lock_and_flush_ordered_range ( struct btrfs_inode * inode , u64 start ,
2019-05-07 10:19:22 +03:00
u64 end ,
struct extent_state * * cached_state )
{
struct btrfs_ordered_extent * ordered ;
2019-07-26 10:47:05 +03:00
struct extent_state * cache = NULL ;
struct extent_state * * cachedp = & cache ;
2019-05-07 10:19:24 +03:00
if ( cached_state )
2019-07-26 10:47:05 +03:00
cachedp = cached_state ;
2019-05-07 10:19:22 +03:00
while ( 1 ) {
2020-02-05 21:09:33 +03:00
lock_extent_bits ( & inode - > io_tree , start , end , cachedp ) ;
2019-05-07 10:19:22 +03:00
ordered = btrfs_lookup_ordered_range ( inode , start ,
end - start + 1 ) ;
2019-05-07 10:19:24 +03:00
if ( ! ordered ) {
/*
* If no external cached_state has been passed then
* decrement the extra ref taken for cachedp since we
* aren ' t exposing it outside of this function
*/
if ( ! cached_state )
2019-07-26 10:47:05 +03:00
refcount_dec ( & cache - > refs ) ;
2019-05-07 10:19:22 +03:00
break ;
2019-05-07 10:19:24 +03:00
}
2020-02-05 21:09:33 +03:00
unlock_extent_cached ( & inode - > io_tree , start , end , cachedp ) ;
2019-05-07 10:19:22 +03:00
btrfs_start_ordered_extent ( & inode - > vfs_inode , ordered , 1 ) ;
btrfs_put_ordered_extent ( ordered ) ;
}
}
2012-09-06 14:01:51 +04:00
int __init ordered_data_init ( void )
{
btrfs_ordered_extent_cache = kmem_cache_create ( " btrfs_ordered_extent " ,
sizeof ( struct btrfs_ordered_extent ) , 0 ,
2016-06-23 21:17:08 +03:00
SLAB_MEM_SPREAD ,
2012-09-06 14:01:51 +04:00
NULL ) ;
if ( ! btrfs_ordered_extent_cache )
return - ENOMEM ;
2012-10-25 13:31:03 +04:00
2012-09-06 14:01:51 +04:00
return 0 ;
}
2018-02-19 19:24:18 +03:00
void __cold ordered_data_exit ( void )
2012-09-06 14:01:51 +04:00
{
2016-01-29 16:36:35 +03:00
kmem_cache_destroy ( btrfs_ordered_extent_cache ) ;
2012-09-06 14:01:51 +04:00
}