License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 08:07:57 -06:00
|
|
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// SPDX-License-Identifier: GPL-2.0
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2018-04-03 11:23:33 -06:00
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2008-01-24 14:13:08 -07:00
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#include <linux/err.h>
|
|
|
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#include <linux/slab.h>
|
2007-08-27 14:49:44 -06:00
|
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|
#include <linux/spinlock.h>
|
2010-12-16 23:21:50 -07:00
|
|
|
#include "ctree.h"
|
2019-03-27 06:24:12 -06:00
|
|
|
#include "volumes.h"
|
2007-08-27 14:49:44 -06:00
|
|
|
#include "extent_map.h"
|
2016-03-10 02:26:59 -07:00
|
|
|
#include "compression.h"
|
2007-08-27 14:49:44 -06:00
|
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|
2007-09-10 17:58:16 -06:00
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|
|
2007-08-27 14:49:44 -06:00
|
|
|
static struct kmem_cache *extent_map_cache;
|
2007-11-27 09:16:35 -07:00
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|
|
2007-11-19 08:22:33 -07:00
|
|
|
int __init extent_map_init(void)
|
2007-08-27 14:49:44 -06:00
|
|
|
{
|
2012-09-07 03:00:48 -06:00
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|
|
extent_map_cache = kmem_cache_create("btrfs_extent_map",
|
2009-04-13 07:33:09 -06:00
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|
|
sizeof(struct extent_map), 0,
|
2016-06-23 12:17:08 -06:00
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|
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SLAB_MEM_SPREAD, NULL);
|
2007-11-19 08:22:33 -07:00
|
|
|
if (!extent_map_cache)
|
|
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|
return -ENOMEM;
|
|
|
|
return 0;
|
2007-08-27 14:49:44 -06:00
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|
|
}
|
|
|
|
|
2018-02-19 09:24:18 -07:00
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void __cold extent_map_exit(void)
|
2007-08-27 14:49:44 -06:00
|
|
|
{
|
2016-01-29 06:36:35 -07:00
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kmem_cache_destroy(extent_map_cache);
|
2007-08-27 14:49:44 -06:00
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|
}
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|
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|
|
2008-06-11 19:52:17 -06:00
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|
/**
|
|
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|
* extent_map_tree_init - initialize extent map tree
|
|
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|
* @tree: tree to initialize
|
|
|
|
*
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|
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|
* Initialize the extent tree @tree. Should be called for each new inode
|
|
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|
* or other user of the extent_map interface.
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|
|
|
*/
|
2011-04-20 16:34:43 -06:00
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void extent_map_tree_init(struct extent_map_tree *tree)
|
2007-08-27 14:49:44 -06:00
|
|
|
{
|
2018-08-22 13:51:52 -06:00
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|
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tree->map = RB_ROOT_CACHED;
|
Btrfs: turbo charge fsync
At least for the vm workload. Currently on fsync we will
1) Truncate all items in the log tree for the given inode if they exist
and
2) Copy all items for a given inode into the log
The problem with this is that for things like VMs you can have lots of
extents from the fragmented writing behavior, and worst yet you may have
only modified a few extents, not the entire thing. This patch fixes this
problem by tracking which transid modified our extent, and then when we do
the tree logging we find all of the extents we've modified in our current
transaction, sort them and commit them. We also only truncate up to the
xattrs of the inode and copy that stuff in normally, and then just drop any
extents in the range we have that exist in the log already. Here are some
numbers of a 50 meg fio job that does random writes and fsync()s after every
write
Original Patched
SATA drive 82KB/s 140KB/s
Fusion drive 431KB/s 2532KB/s
So around 2-6 times faster depending on your hardware. There are a few
corner cases, for example if you truncate at all we have to do it the old
way since there is no way to be sure what is in the log is ok. This
probably could be done smarter, but if you write-fsync-truncate-write-fsync
you deserve what you get. All this work is in RAM of course so if your
inode gets evicted from cache and you read it in and fsync it we'll do it
the slow way if we are still in the same transaction that we last modified
the inode in.
The biggest cool part of this is that it requires no changes to the recovery
code, so if you fsync with this patch and crash and load an old kernel, it
will run the recovery and be a-ok. I have tested this pretty thoroughly
with an fsync tester and everything comes back fine, as well as xfstests.
Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-08-17 11:14:17 -06:00
|
|
|
INIT_LIST_HEAD(&tree->modified_extents);
|
2009-09-02 14:24:52 -06:00
|
|
|
rwlock_init(&tree->lock);
|
2007-08-27 14:49:44 -06:00
|
|
|
}
|
|
|
|
|
2008-06-11 19:52:17 -06:00
|
|
|
/**
|
|
|
|
* alloc_extent_map - allocate new extent map structure
|
|
|
|
*
|
|
|
|
* Allocate a new extent_map structure. The new structure is
|
|
|
|
* returned with a reference count of one and needs to be
|
|
|
|
* freed using free_extent_map()
|
|
|
|
*/
|
2011-04-20 16:48:27 -06:00
|
|
|
struct extent_map *alloc_extent_map(void)
|
2007-08-27 14:49:44 -06:00
|
|
|
{
|
|
|
|
struct extent_map *em;
|
2012-10-11 14:54:30 -06:00
|
|
|
em = kmem_cache_zalloc(extent_map_cache, GFP_NOFS);
|
2011-02-13 17:45:29 -07:00
|
|
|
if (!em)
|
|
|
|
return NULL;
|
2014-02-25 07:15:12 -07:00
|
|
|
RB_CLEAR_NODE(&em->rb_node);
|
2008-01-24 14:13:08 -07:00
|
|
|
em->flags = 0;
|
2010-12-16 23:21:50 -07:00
|
|
|
em->compress_type = BTRFS_COMPRESS_NONE;
|
Btrfs: turbo charge fsync
At least for the vm workload. Currently on fsync we will
1) Truncate all items in the log tree for the given inode if they exist
and
2) Copy all items for a given inode into the log
The problem with this is that for things like VMs you can have lots of
extents from the fragmented writing behavior, and worst yet you may have
only modified a few extents, not the entire thing. This patch fixes this
problem by tracking which transid modified our extent, and then when we do
the tree logging we find all of the extents we've modified in our current
transaction, sort them and commit them. We also only truncate up to the
xattrs of the inode and copy that stuff in normally, and then just drop any
extents in the range we have that exist in the log already. Here are some
numbers of a 50 meg fio job that does random writes and fsync()s after every
write
Original Patched
SATA drive 82KB/s 140KB/s
Fusion drive 431KB/s 2532KB/s
So around 2-6 times faster depending on your hardware. There are a few
corner cases, for example if you truncate at all we have to do it the old
way since there is no way to be sure what is in the log is ok. This
probably could be done smarter, but if you write-fsync-truncate-write-fsync
you deserve what you get. All this work is in RAM of course so if your
inode gets evicted from cache and you read it in and fsync it we'll do it
the slow way if we are still in the same transaction that we last modified
the inode in.
The biggest cool part of this is that it requires no changes to the recovery
code, so if you fsync with this patch and crash and load an old kernel, it
will run the recovery and be a-ok. I have tested this pretty thoroughly
with an fsync tester and everything comes back fine, as well as xfstests.
Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-08-17 11:14:17 -06:00
|
|
|
em->generation = 0;
|
2017-03-03 01:55:12 -07:00
|
|
|
refcount_set(&em->refs, 1);
|
Btrfs: turbo charge fsync
At least for the vm workload. Currently on fsync we will
1) Truncate all items in the log tree for the given inode if they exist
and
2) Copy all items for a given inode into the log
The problem with this is that for things like VMs you can have lots of
extents from the fragmented writing behavior, and worst yet you may have
only modified a few extents, not the entire thing. This patch fixes this
problem by tracking which transid modified our extent, and then when we do
the tree logging we find all of the extents we've modified in our current
transaction, sort them and commit them. We also only truncate up to the
xattrs of the inode and copy that stuff in normally, and then just drop any
extents in the range we have that exist in the log already. Here are some
numbers of a 50 meg fio job that does random writes and fsync()s after every
write
Original Patched
SATA drive 82KB/s 140KB/s
Fusion drive 431KB/s 2532KB/s
So around 2-6 times faster depending on your hardware. There are a few
corner cases, for example if you truncate at all we have to do it the old
way since there is no way to be sure what is in the log is ok. This
probably could be done smarter, but if you write-fsync-truncate-write-fsync
you deserve what you get. All this work is in RAM of course so if your
inode gets evicted from cache and you read it in and fsync it we'll do it
the slow way if we are still in the same transaction that we last modified
the inode in.
The biggest cool part of this is that it requires no changes to the recovery
code, so if you fsync with this patch and crash and load an old kernel, it
will run the recovery and be a-ok. I have tested this pretty thoroughly
with an fsync tester and everything comes back fine, as well as xfstests.
Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-08-17 11:14:17 -06:00
|
|
|
INIT_LIST_HEAD(&em->list);
|
2007-08-27 14:49:44 -06:00
|
|
|
return em;
|
|
|
|
}
|
|
|
|
|
2008-06-11 19:52:17 -06:00
|
|
|
/**
|
|
|
|
* free_extent_map - drop reference count of an extent_map
|
2016-05-19 19:18:45 -06:00
|
|
|
* @em: extent map being released
|
2008-06-11 19:52:17 -06:00
|
|
|
*
|
|
|
|
* Drops the reference out on @em by one and free the structure
|
|
|
|
* if the reference count hits zero.
|
|
|
|
*/
|
2007-08-27 14:49:44 -06:00
|
|
|
void free_extent_map(struct extent_map *em)
|
|
|
|
{
|
2007-08-30 09:54:02 -06:00
|
|
|
if (!em)
|
|
|
|
return;
|
2017-03-03 01:55:12 -07:00
|
|
|
WARN_ON(refcount_read(&em->refs) == 0);
|
|
|
|
if (refcount_dec_and_test(&em->refs)) {
|
2014-02-25 07:15:12 -07:00
|
|
|
WARN_ON(extent_map_in_tree(em));
|
Btrfs: turbo charge fsync
At least for the vm workload. Currently on fsync we will
1) Truncate all items in the log tree for the given inode if they exist
and
2) Copy all items for a given inode into the log
The problem with this is that for things like VMs you can have lots of
extents from the fragmented writing behavior, and worst yet you may have
only modified a few extents, not the entire thing. This patch fixes this
problem by tracking which transid modified our extent, and then when we do
the tree logging we find all of the extents we've modified in our current
transaction, sort them and commit them. We also only truncate up to the
xattrs of the inode and copy that stuff in normally, and then just drop any
extents in the range we have that exist in the log already. Here are some
numbers of a 50 meg fio job that does random writes and fsync()s after every
write
Original Patched
SATA drive 82KB/s 140KB/s
Fusion drive 431KB/s 2532KB/s
So around 2-6 times faster depending on your hardware. There are a few
corner cases, for example if you truncate at all we have to do it the old
way since there is no way to be sure what is in the log is ok. This
probably could be done smarter, but if you write-fsync-truncate-write-fsync
you deserve what you get. All this work is in RAM of course so if your
inode gets evicted from cache and you read it in and fsync it we'll do it
the slow way if we are still in the same transaction that we last modified
the inode in.
The biggest cool part of this is that it requires no changes to the recovery
code, so if you fsync with this patch and crash and load an old kernel, it
will run the recovery and be a-ok. I have tested this pretty thoroughly
with an fsync tester and everything comes back fine, as well as xfstests.
Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-08-17 11:14:17 -06:00
|
|
|
WARN_ON(!list_empty(&em->list));
|
2014-06-18 20:42:52 -06:00
|
|
|
if (test_bit(EXTENT_FLAG_FS_MAPPING, &em->flags))
|
2015-06-03 08:55:48 -06:00
|
|
|
kfree(em->map_lookup);
|
2007-08-27 14:49:44 -06:00
|
|
|
kmem_cache_free(extent_map_cache, em);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2013-11-24 20:23:51 -07:00
|
|
|
/* simple helper to do math around the end of an extent, handling wrap */
|
|
|
|
static u64 range_end(u64 start, u64 len)
|
|
|
|
{
|
|
|
|
if (start + len < start)
|
|
|
|
return (u64)-1;
|
|
|
|
return start + len;
|
|
|
|
}
|
|
|
|
|
2018-08-22 13:51:52 -06:00
|
|
|
static int tree_insert(struct rb_root_cached *root, struct extent_map *em)
|
2007-08-27 14:49:44 -06:00
|
|
|
{
|
2018-08-22 13:51:52 -06:00
|
|
|
struct rb_node **p = &root->rb_root.rb_node;
|
2009-01-05 19:25:51 -07:00
|
|
|
struct rb_node *parent = NULL;
|
2013-11-24 20:23:51 -07:00
|
|
|
struct extent_map *entry = NULL;
|
|
|
|
struct rb_node *orig_parent = NULL;
|
|
|
|
u64 end = range_end(em->start, em->len);
|
2018-08-22 13:51:52 -06:00
|
|
|
bool leftmost = true;
|
2007-08-27 14:49:44 -06:00
|
|
|
|
2009-01-05 19:25:51 -07:00
|
|
|
while (*p) {
|
2007-08-27 14:49:44 -06:00
|
|
|
parent = *p;
|
2008-01-24 14:13:08 -07:00
|
|
|
entry = rb_entry(parent, struct extent_map, rb_node);
|
|
|
|
|
2018-08-22 13:51:52 -06:00
|
|
|
if (em->start < entry->start) {
|
2007-08-27 14:49:44 -06:00
|
|
|
p = &(*p)->rb_left;
|
2018-08-22 13:51:52 -06:00
|
|
|
} else if (em->start >= extent_map_end(entry)) {
|
2007-08-27 14:49:44 -06:00
|
|
|
p = &(*p)->rb_right;
|
2018-08-22 13:51:52 -06:00
|
|
|
leftmost = false;
|
|
|
|
} else {
|
2013-11-24 20:23:51 -07:00
|
|
|
return -EEXIST;
|
2018-08-22 13:51:52 -06:00
|
|
|
}
|
2007-08-27 14:49:44 -06:00
|
|
|
}
|
|
|
|
|
2013-11-24 20:23:51 -07:00
|
|
|
orig_parent = parent;
|
|
|
|
while (parent && em->start >= extent_map_end(entry)) {
|
|
|
|
parent = rb_next(parent);
|
|
|
|
entry = rb_entry(parent, struct extent_map, rb_node);
|
|
|
|
}
|
|
|
|
if (parent)
|
|
|
|
if (end > entry->start && em->start < extent_map_end(entry))
|
|
|
|
return -EEXIST;
|
|
|
|
|
|
|
|
parent = orig_parent;
|
|
|
|
entry = rb_entry(parent, struct extent_map, rb_node);
|
|
|
|
while (parent && em->start < entry->start) {
|
|
|
|
parent = rb_prev(parent);
|
|
|
|
entry = rb_entry(parent, struct extent_map, rb_node);
|
|
|
|
}
|
|
|
|
if (parent)
|
|
|
|
if (end > entry->start && em->start < extent_map_end(entry))
|
|
|
|
return -EEXIST;
|
|
|
|
|
|
|
|
rb_link_node(&em->rb_node, orig_parent, p);
|
2018-08-22 13:51:52 -06:00
|
|
|
rb_insert_color_cached(&em->rb_node, root, leftmost);
|
2013-11-24 20:23:51 -07:00
|
|
|
return 0;
|
2007-08-27 14:49:44 -06:00
|
|
|
}
|
|
|
|
|
2008-09-29 13:18:18 -06:00
|
|
|
/*
|
|
|
|
* search through the tree for an extent_map with a given offset. If
|
|
|
|
* it can't be found, try to find some neighboring extents
|
|
|
|
*/
|
2007-08-27 14:49:44 -06:00
|
|
|
static struct rb_node *__tree_search(struct rb_root *root, u64 offset,
|
2008-01-22 14:47:59 -07:00
|
|
|
struct rb_node **prev_ret,
|
|
|
|
struct rb_node **next_ret)
|
2007-08-27 14:49:44 -06:00
|
|
|
{
|
2009-01-05 19:25:51 -07:00
|
|
|
struct rb_node *n = root->rb_node;
|
2007-08-27 14:49:44 -06:00
|
|
|
struct rb_node *prev = NULL;
|
2008-01-22 14:47:59 -07:00
|
|
|
struct rb_node *orig_prev = NULL;
|
2008-01-24 14:13:08 -07:00
|
|
|
struct extent_map *entry;
|
|
|
|
struct extent_map *prev_entry = NULL;
|
2007-08-27 14:49:44 -06:00
|
|
|
|
2009-01-05 19:25:51 -07:00
|
|
|
while (n) {
|
2008-01-24 14:13:08 -07:00
|
|
|
entry = rb_entry(n, struct extent_map, rb_node);
|
2007-08-27 14:49:44 -06:00
|
|
|
prev = n;
|
|
|
|
prev_entry = entry;
|
|
|
|
|
|
|
|
if (offset < entry->start)
|
|
|
|
n = n->rb_left;
|
2008-01-24 14:13:08 -07:00
|
|
|
else if (offset >= extent_map_end(entry))
|
2007-08-27 14:49:44 -06:00
|
|
|
n = n->rb_right;
|
|
|
|
else
|
|
|
|
return n;
|
|
|
|
}
|
2008-01-22 14:47:59 -07:00
|
|
|
|
|
|
|
if (prev_ret) {
|
|
|
|
orig_prev = prev;
|
2009-01-05 19:25:51 -07:00
|
|
|
while (prev && offset >= extent_map_end(prev_entry)) {
|
2008-01-22 14:47:59 -07:00
|
|
|
prev = rb_next(prev);
|
2008-01-24 14:13:08 -07:00
|
|
|
prev_entry = rb_entry(prev, struct extent_map, rb_node);
|
2008-01-22 14:47:59 -07:00
|
|
|
}
|
|
|
|
*prev_ret = prev;
|
|
|
|
prev = orig_prev;
|
|
|
|
}
|
|
|
|
|
|
|
|
if (next_ret) {
|
2008-01-24 14:13:08 -07:00
|
|
|
prev_entry = rb_entry(prev, struct extent_map, rb_node);
|
2009-01-05 19:25:51 -07:00
|
|
|
while (prev && offset < prev_entry->start) {
|
2008-01-22 14:47:59 -07:00
|
|
|
prev = rb_prev(prev);
|
2008-01-24 14:13:08 -07:00
|
|
|
prev_entry = rb_entry(prev, struct extent_map, rb_node);
|
2008-01-22 14:47:59 -07:00
|
|
|
}
|
|
|
|
*next_ret = prev;
|
2007-08-27 14:49:44 -06:00
|
|
|
}
|
|
|
|
return NULL;
|
|
|
|
}
|
|
|
|
|
2008-09-29 13:18:18 -06:00
|
|
|
/* check to see if two extent_map structs are adjacent and safe to merge */
|
2008-01-24 14:13:08 -07:00
|
|
|
static int mergable_maps(struct extent_map *prev, struct extent_map *next)
|
2007-08-27 14:49:44 -06:00
|
|
|
{
|
2008-07-18 10:01:11 -06:00
|
|
|
if (test_bit(EXTENT_FLAG_PINNED, &prev->flags))
|
|
|
|
return 0;
|
|
|
|
|
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 12:49:59 -06:00
|
|
|
/*
|
|
|
|
* don't merge compressed extents, we need to know their
|
|
|
|
* actual size
|
|
|
|
*/
|
|
|
|
if (test_bit(EXTENT_FLAG_COMPRESSED, &prev->flags))
|
|
|
|
return 0;
|
|
|
|
|
2013-01-24 10:02:07 -07:00
|
|
|
if (test_bit(EXTENT_FLAG_LOGGING, &prev->flags) ||
|
|
|
|
test_bit(EXTENT_FLAG_LOGGING, &next->flags))
|
|
|
|
return 0;
|
|
|
|
|
2013-04-05 14:51:15 -06:00
|
|
|
/*
|
|
|
|
* We don't want to merge stuff that hasn't been written to the log yet
|
|
|
|
* since it may not reflect exactly what is on disk, and that would be
|
|
|
|
* bad.
|
|
|
|
*/
|
|
|
|
if (!list_empty(&prev->list) || !list_empty(&next->list))
|
|
|
|
return 0;
|
|
|
|
|
2019-01-08 07:53:46 -07:00
|
|
|
ASSERT(next->block_start != EXTENT_MAP_DELALLOC &&
|
|
|
|
prev->block_start != EXTENT_MAP_DELALLOC);
|
|
|
|
|
2019-05-10 09:48:30 -06:00
|
|
|
if (prev->map_lookup || next->map_lookup)
|
|
|
|
ASSERT(test_bit(EXTENT_FLAG_FS_MAPPING, &prev->flags) &&
|
|
|
|
test_bit(EXTENT_FLAG_FS_MAPPING, &next->flags));
|
|
|
|
|
2008-01-24 14:13:08 -07:00
|
|
|
if (extent_map_end(prev) == next->start &&
|
|
|
|
prev->flags == next->flags &&
|
2019-05-10 09:48:30 -06:00
|
|
|
prev->map_lookup == next->map_lookup &&
|
2008-01-24 14:13:08 -07:00
|
|
|
((next->block_start == EXTENT_MAP_HOLE &&
|
|
|
|
prev->block_start == EXTENT_MAP_HOLE) ||
|
|
|
|
(next->block_start == EXTENT_MAP_INLINE &&
|
|
|
|
prev->block_start == EXTENT_MAP_INLINE) ||
|
|
|
|
(next->block_start < EXTENT_MAP_LAST_BYTE - 1 &&
|
|
|
|
next->block_start == extent_map_block_end(prev)))) {
|
|
|
|
return 1;
|
|
|
|
}
|
2007-08-27 14:49:44 -06:00
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2011-07-13 21:18:33 -06:00
|
|
|
static void try_merge_map(struct extent_map_tree *tree, struct extent_map *em)
|
2009-09-11 10:27:37 -06:00
|
|
|
{
|
|
|
|
struct extent_map *merge = NULL;
|
|
|
|
struct rb_node *rb;
|
|
|
|
|
Btrfs: fix race between using extent maps and merging them
We have a few cases where we allow an extent map that is in an extent map
tree to be merged with other extents in the tree. Such cases include the
unpinning of an extent after the respective ordered extent completed or
after logging an extent during a fast fsync. This can lead to subtle and
dangerous problems because when doing the merge some other task might be
using the same extent map and as consequence see an inconsistent state of
the extent map - for example sees the new length but has seen the old start
offset.
With luck this triggers a BUG_ON(), and not some silent bug, such as the
following one in __do_readpage():
$ cat -n fs/btrfs/extent_io.c
3061 static int __do_readpage(struct extent_io_tree *tree,
3062 struct page *page,
(...)
3127 em = __get_extent_map(inode, page, pg_offset, cur,
3128 end - cur + 1, get_extent, em_cached);
3129 if (IS_ERR_OR_NULL(em)) {
3130 SetPageError(page);
3131 unlock_extent(tree, cur, end);
3132 break;
3133 }
3134 extent_offset = cur - em->start;
3135 BUG_ON(extent_map_end(em) <= cur);
(...)
Consider the following example scenario, where we end up hitting the
BUG_ON() in __do_readpage().
We have an inode with a size of 8KiB and 2 extent maps:
extent A: file offset 0, length 4KiB, disk_bytenr = X, persisted on disk by
a previous transaction
extent B: file offset 4KiB, length 4KiB, disk_bytenr = X + 4KiB, not yet
persisted but writeback started for it already. The extent map
is pinned since there's writeback and an ordered extent in
progress, so it can not be merged with extent map A yet
The following sequence of steps leads to the BUG_ON():
1) The ordered extent for extent B completes, the respective page gets its
writeback bit cleared and the extent map is unpinned, at that point it
is not yet merged with extent map A because it's in the list of modified
extents;
2) Due to memory pressure, or some other reason, the MM subsystem releases
the page corresponding to extent B - btrfs_releasepage() is called and
returns 1, meaning the page can be released as it's not dirty, not under
writeback anymore and the extent range is not locked in the inode's
iotree. However the extent map is not released, either because we are
not in a context that allows memory allocations to block or because the
inode's size is smaller than 16MiB - in this case our inode has a size
of 8KiB;
3) Task B needs to read extent B and ends up __do_readpage() through the
btrfs_readpage() callback. At __do_readpage() it gets a reference to
extent map B;
4) Task A, doing a fast fsync, calls clear_em_loggin() against extent map B
while holding the write lock on the inode's extent map tree - this
results in try_merge_map() being called and since it's possible to merge
extent map B with extent map A now (the extent map B was removed from
the list of modified extents), the merging begins - it sets extent map
B's start offset to 0 (was 4KiB), but before it increments the map's
length to 8KiB (4kb + 4KiB), task A is at:
BUG_ON(extent_map_end(em) <= cur);
The call to extent_map_end() sees the extent map has a start of 0
and a length still at 4KiB, so it returns 4KiB and 'cur' is 4KiB, so
the BUG_ON() is triggered.
So it's dangerous to modify an extent map that is in the tree, because some
other task might have got a reference to it before and still using it, and
needs to see a consistent map while using it. Generally this is very rare
since most paths that lookup and use extent maps also have the file range
locked in the inode's iotree. The fsync path is pretty much the only
exception where we don't do it to avoid serialization with concurrent
reads.
Fix this by not allowing an extent map do be merged if if it's being used
by tasks other then the one attempting to merge the extent map (when the
reference count of the extent map is greater than 2).
Reported-by: ryusuke1925 <st13s20@gm.ibaraki-ct.ac.jp>
Reported-by: Koki Mitani <koki.mitani.xg@hco.ntt.co.jp>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=206211
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-01-31 07:06:07 -07:00
|
|
|
/*
|
|
|
|
* We can't modify an extent map that is in the tree and that is being
|
|
|
|
* used by another task, as it can cause that other task to see it in
|
|
|
|
* inconsistent state during the merging. We always have 1 reference for
|
|
|
|
* the tree and 1 for this task (which is unpinning the extent map or
|
|
|
|
* clearing the logging flag), so anything > 2 means it's being used by
|
|
|
|
* other tasks too.
|
|
|
|
*/
|
|
|
|
if (refcount_read(&em->refs) > 2)
|
|
|
|
return;
|
|
|
|
|
2009-09-11 10:27:37 -06:00
|
|
|
if (em->start != 0) {
|
|
|
|
rb = rb_prev(&em->rb_node);
|
|
|
|
if (rb)
|
|
|
|
merge = rb_entry(rb, struct extent_map, rb_node);
|
|
|
|
if (rb && mergable_maps(merge, em)) {
|
|
|
|
em->start = merge->start;
|
2012-10-11 14:54:30 -06:00
|
|
|
em->orig_start = merge->orig_start;
|
2009-09-11 10:27:37 -06:00
|
|
|
em->len += merge->len;
|
|
|
|
em->block_len += merge->block_len;
|
|
|
|
em->block_start = merge->block_start;
|
2012-10-11 14:54:30 -06:00
|
|
|
em->mod_len = (em->mod_len + em->mod_start) - merge->mod_start;
|
|
|
|
em->mod_start = merge->mod_start;
|
|
|
|
em->generation = max(em->generation, merge->generation);
|
Btrfs: turbo charge fsync
At least for the vm workload. Currently on fsync we will
1) Truncate all items in the log tree for the given inode if they exist
and
2) Copy all items for a given inode into the log
The problem with this is that for things like VMs you can have lots of
extents from the fragmented writing behavior, and worst yet you may have
only modified a few extents, not the entire thing. This patch fixes this
problem by tracking which transid modified our extent, and then when we do
the tree logging we find all of the extents we've modified in our current
transaction, sort them and commit them. We also only truncate up to the
xattrs of the inode and copy that stuff in normally, and then just drop any
extents in the range we have that exist in the log already. Here are some
numbers of a 50 meg fio job that does random writes and fsync()s after every
write
Original Patched
SATA drive 82KB/s 140KB/s
Fusion drive 431KB/s 2532KB/s
So around 2-6 times faster depending on your hardware. There are a few
corner cases, for example if you truncate at all we have to do it the old
way since there is no way to be sure what is in the log is ok. This
probably could be done smarter, but if you write-fsync-truncate-write-fsync
you deserve what you get. All this work is in RAM of course so if your
inode gets evicted from cache and you read it in and fsync it we'll do it
the slow way if we are still in the same transaction that we last modified
the inode in.
The biggest cool part of this is that it requires no changes to the recovery
code, so if you fsync with this patch and crash and load an old kernel, it
will run the recovery and be a-ok. I have tested this pretty thoroughly
with an fsync tester and everything comes back fine, as well as xfstests.
Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-08-17 11:14:17 -06:00
|
|
|
|
2018-08-22 13:51:52 -06:00
|
|
|
rb_erase_cached(&merge->rb_node, &tree->map);
|
2014-02-25 07:15:12 -07:00
|
|
|
RB_CLEAR_NODE(&merge->rb_node);
|
2009-09-11 10:27:37 -06:00
|
|
|
free_extent_map(merge);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
rb = rb_next(&em->rb_node);
|
|
|
|
if (rb)
|
|
|
|
merge = rb_entry(rb, struct extent_map, rb_node);
|
|
|
|
if (rb && mergable_maps(em, merge)) {
|
|
|
|
em->len += merge->len;
|
2013-11-30 04:28:35 -07:00
|
|
|
em->block_len += merge->block_len;
|
2018-08-22 13:51:52 -06:00
|
|
|
rb_erase_cached(&merge->rb_node, &tree->map);
|
2014-02-25 07:15:12 -07:00
|
|
|
RB_CLEAR_NODE(&merge->rb_node);
|
2012-10-11 14:54:30 -06:00
|
|
|
em->mod_len = (merge->mod_start + merge->mod_len) - em->mod_start;
|
|
|
|
em->generation = max(em->generation, merge->generation);
|
2009-09-11 10:27:37 -06:00
|
|
|
free_extent_map(merge);
|
|
|
|
}
|
2011-07-13 21:18:33 -06:00
|
|
|
}
|
|
|
|
|
Btrfs: turbo charge fsync
At least for the vm workload. Currently on fsync we will
1) Truncate all items in the log tree for the given inode if they exist
and
2) Copy all items for a given inode into the log
The problem with this is that for things like VMs you can have lots of
extents from the fragmented writing behavior, and worst yet you may have
only modified a few extents, not the entire thing. This patch fixes this
problem by tracking which transid modified our extent, and then when we do
the tree logging we find all of the extents we've modified in our current
transaction, sort them and commit them. We also only truncate up to the
xattrs of the inode and copy that stuff in normally, and then just drop any
extents in the range we have that exist in the log already. Here are some
numbers of a 50 meg fio job that does random writes and fsync()s after every
write
Original Patched
SATA drive 82KB/s 140KB/s
Fusion drive 431KB/s 2532KB/s
So around 2-6 times faster depending on your hardware. There are a few
corner cases, for example if you truncate at all we have to do it the old
way since there is no way to be sure what is in the log is ok. This
probably could be done smarter, but if you write-fsync-truncate-write-fsync
you deserve what you get. All this work is in RAM of course so if your
inode gets evicted from cache and you read it in and fsync it we'll do it
the slow way if we are still in the same transaction that we last modified
the inode in.
The biggest cool part of this is that it requires no changes to the recovery
code, so if you fsync with this patch and crash and load an old kernel, it
will run the recovery and be a-ok. I have tested this pretty thoroughly
with an fsync tester and everything comes back fine, as well as xfstests.
Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-08-17 11:14:17 -06:00
|
|
|
/**
|
2012-10-30 03:13:52 -06:00
|
|
|
* unpin_extent_cache - unpin an extent from the cache
|
Btrfs: turbo charge fsync
At least for the vm workload. Currently on fsync we will
1) Truncate all items in the log tree for the given inode if they exist
and
2) Copy all items for a given inode into the log
The problem with this is that for things like VMs you can have lots of
extents from the fragmented writing behavior, and worst yet you may have
only modified a few extents, not the entire thing. This patch fixes this
problem by tracking which transid modified our extent, and then when we do
the tree logging we find all of the extents we've modified in our current
transaction, sort them and commit them. We also only truncate up to the
xattrs of the inode and copy that stuff in normally, and then just drop any
extents in the range we have that exist in the log already. Here are some
numbers of a 50 meg fio job that does random writes and fsync()s after every
write
Original Patched
SATA drive 82KB/s 140KB/s
Fusion drive 431KB/s 2532KB/s
So around 2-6 times faster depending on your hardware. There are a few
corner cases, for example if you truncate at all we have to do it the old
way since there is no way to be sure what is in the log is ok. This
probably could be done smarter, but if you write-fsync-truncate-write-fsync
you deserve what you get. All this work is in RAM of course so if your
inode gets evicted from cache and you read it in and fsync it we'll do it
the slow way if we are still in the same transaction that we last modified
the inode in.
The biggest cool part of this is that it requires no changes to the recovery
code, so if you fsync with this patch and crash and load an old kernel, it
will run the recovery and be a-ok. I have tested this pretty thoroughly
with an fsync tester and everything comes back fine, as well as xfstests.
Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-08-17 11:14:17 -06:00
|
|
|
* @tree: tree to unpin the extent in
|
|
|
|
* @start: logical offset in the file
|
|
|
|
* @len: length of the extent
|
|
|
|
* @gen: generation that this extent has been modified in
|
|
|
|
*
|
|
|
|
* Called after an extent has been written to disk properly. Set the generation
|
|
|
|
* to the generation that actually added the file item to the inode so we know
|
|
|
|
* we need to sync this extent when we call fsync().
|
|
|
|
*/
|
|
|
|
int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len,
|
|
|
|
u64 gen)
|
2011-07-13 21:18:33 -06:00
|
|
|
{
|
|
|
|
int ret = 0;
|
|
|
|
struct extent_map *em;
|
2012-08-27 10:52:20 -06:00
|
|
|
bool prealloc = false;
|
2011-07-13 21:18:33 -06:00
|
|
|
|
|
|
|
write_lock(&tree->lock);
|
|
|
|
em = lookup_extent_mapping(tree, start, len);
|
|
|
|
|
|
|
|
WARN_ON(!em || em->start != start);
|
|
|
|
|
|
|
|
if (!em)
|
|
|
|
goto out;
|
|
|
|
|
Btrfs: turbo charge fsync
At least for the vm workload. Currently on fsync we will
1) Truncate all items in the log tree for the given inode if they exist
and
2) Copy all items for a given inode into the log
The problem with this is that for things like VMs you can have lots of
extents from the fragmented writing behavior, and worst yet you may have
only modified a few extents, not the entire thing. This patch fixes this
problem by tracking which transid modified our extent, and then when we do
the tree logging we find all of the extents we've modified in our current
transaction, sort them and commit them. We also only truncate up to the
xattrs of the inode and copy that stuff in normally, and then just drop any
extents in the range we have that exist in the log already. Here are some
numbers of a 50 meg fio job that does random writes and fsync()s after every
write
Original Patched
SATA drive 82KB/s 140KB/s
Fusion drive 431KB/s 2532KB/s
So around 2-6 times faster depending on your hardware. There are a few
corner cases, for example if you truncate at all we have to do it the old
way since there is no way to be sure what is in the log is ok. This
probably could be done smarter, but if you write-fsync-truncate-write-fsync
you deserve what you get. All this work is in RAM of course so if your
inode gets evicted from cache and you read it in and fsync it we'll do it
the slow way if we are still in the same transaction that we last modified
the inode in.
The biggest cool part of this is that it requires no changes to the recovery
code, so if you fsync with this patch and crash and load an old kernel, it
will run the recovery and be a-ok. I have tested this pretty thoroughly
with an fsync tester and everything comes back fine, as well as xfstests.
Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-08-17 11:14:17 -06:00
|
|
|
em->generation = gen;
|
2011-07-13 21:18:33 -06:00
|
|
|
clear_bit(EXTENT_FLAG_PINNED, &em->flags);
|
2012-08-27 10:52:20 -06:00
|
|
|
em->mod_start = em->start;
|
|
|
|
em->mod_len = em->len;
|
|
|
|
|
2012-12-03 08:58:15 -07:00
|
|
|
if (test_bit(EXTENT_FLAG_FILLING, &em->flags)) {
|
2012-08-27 10:52:20 -06:00
|
|
|
prealloc = true;
|
2012-12-03 08:58:15 -07:00
|
|
|
clear_bit(EXTENT_FLAG_FILLING, &em->flags);
|
2012-08-27 10:52:20 -06:00
|
|
|
}
|
2011-07-13 21:18:33 -06:00
|
|
|
|
|
|
|
try_merge_map(tree, em);
|
2012-08-27 10:52:20 -06:00
|
|
|
|
|
|
|
if (prealloc) {
|
|
|
|
em->mod_start = em->start;
|
|
|
|
em->mod_len = em->len;
|
|
|
|
}
|
|
|
|
|
2009-09-11 10:27:37 -06:00
|
|
|
free_extent_map(em);
|
|
|
|
out:
|
|
|
|
write_unlock(&tree->lock);
|
|
|
|
return ret;
|
|
|
|
|
|
|
|
}
|
|
|
|
|
2013-01-24 10:02:07 -07:00
|
|
|
void clear_em_logging(struct extent_map_tree *tree, struct extent_map *em)
|
|
|
|
{
|
|
|
|
clear_bit(EXTENT_FLAG_LOGGING, &em->flags);
|
2014-02-25 07:15:12 -07:00
|
|
|
if (extent_map_in_tree(em))
|
2013-01-28 07:45:20 -07:00
|
|
|
try_merge_map(tree, em);
|
2013-01-24 10:02:07 -07:00
|
|
|
}
|
|
|
|
|
2014-02-25 07:15:13 -07:00
|
|
|
static inline void setup_extent_mapping(struct extent_map_tree *tree,
|
|
|
|
struct extent_map *em,
|
|
|
|
int modified)
|
|
|
|
{
|
2017-03-03 01:55:12 -07:00
|
|
|
refcount_inc(&em->refs);
|
2014-02-25 07:15:13 -07:00
|
|
|
em->mod_start = em->start;
|
|
|
|
em->mod_len = em->len;
|
|
|
|
|
|
|
|
if (modified)
|
|
|
|
list_move(&em->list, &tree->modified_extents);
|
|
|
|
else
|
|
|
|
try_merge_map(tree, em);
|
|
|
|
}
|
|
|
|
|
2019-03-27 06:24:12 -06:00
|
|
|
static void extent_map_device_set_bits(struct extent_map *em, unsigned bits)
|
|
|
|
{
|
|
|
|
struct map_lookup *map = em->map_lookup;
|
|
|
|
u64 stripe_size = em->orig_block_len;
|
|
|
|
int i;
|
|
|
|
|
|
|
|
for (i = 0; i < map->num_stripes; i++) {
|
|
|
|
struct btrfs_bio_stripe *stripe = &map->stripes[i];
|
|
|
|
struct btrfs_device *device = stripe->dev;
|
|
|
|
|
|
|
|
set_extent_bits_nowait(&device->alloc_state, stripe->physical,
|
|
|
|
stripe->physical + stripe_size - 1, bits);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
static void extent_map_device_clear_bits(struct extent_map *em, unsigned bits)
|
|
|
|
{
|
|
|
|
struct map_lookup *map = em->map_lookup;
|
|
|
|
u64 stripe_size = em->orig_block_len;
|
|
|
|
int i;
|
|
|
|
|
|
|
|
for (i = 0; i < map->num_stripes; i++) {
|
|
|
|
struct btrfs_bio_stripe *stripe = &map->stripes[i];
|
|
|
|
struct btrfs_device *device = stripe->dev;
|
|
|
|
|
|
|
|
__clear_extent_bit(&device->alloc_state, stripe->physical,
|
|
|
|
stripe->physical + stripe_size - 1, bits,
|
|
|
|
0, 0, NULL, GFP_NOWAIT, NULL);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2008-06-11 19:52:17 -06:00
|
|
|
/**
|
|
|
|
* add_extent_mapping - add new extent map to the extent tree
|
|
|
|
* @tree: tree to insert new map in
|
|
|
|
* @em: map to insert
|
|
|
|
*
|
|
|
|
* Insert @em into @tree or perform a simple forward/backward merge with
|
|
|
|
* existing mappings. The extent_map struct passed in will be inserted
|
|
|
|
* into the tree directly, with an additional reference taken, or a
|
2011-03-30 19:57:33 -06:00
|
|
|
* reference dropped if the merge attempt was successful.
|
2007-08-27 14:49:44 -06:00
|
|
|
*/
|
|
|
|
int add_extent_mapping(struct extent_map_tree *tree,
|
2013-04-05 14:51:15 -06:00
|
|
|
struct extent_map *em, int modified)
|
2007-08-27 14:49:44 -06:00
|
|
|
{
|
|
|
|
int ret = 0;
|
|
|
|
|
2019-03-27 09:19:55 -06:00
|
|
|
lockdep_assert_held_write(&tree->lock);
|
|
|
|
|
2013-11-24 20:23:51 -07:00
|
|
|
ret = tree_insert(&tree->map, em);
|
|
|
|
if (ret)
|
2007-08-27 14:49:44 -06:00
|
|
|
goto out;
|
2013-11-24 20:23:51 -07:00
|
|
|
|
2014-02-25 07:15:13 -07:00
|
|
|
setup_extent_mapping(tree, em, modified);
|
2019-03-27 06:24:16 -06:00
|
|
|
if (test_bit(EXTENT_FLAG_FS_MAPPING, &em->flags)) {
|
2019-03-27 06:24:12 -06:00
|
|
|
extent_map_device_set_bits(em, CHUNK_ALLOCATED);
|
2019-03-27 06:24:16 -06:00
|
|
|
extent_map_device_clear_bits(em, CHUNK_TRIMMED);
|
|
|
|
}
|
2007-08-27 14:49:44 -06:00
|
|
|
out:
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
2013-04-25 14:41:01 -06:00
|
|
|
static struct extent_map *
|
|
|
|
__lookup_extent_mapping(struct extent_map_tree *tree,
|
|
|
|
u64 start, u64 len, int strict)
|
2007-08-27 14:49:44 -06:00
|
|
|
{
|
|
|
|
struct extent_map *em;
|
|
|
|
struct rb_node *rb_node;
|
2008-06-10 08:21:04 -06:00
|
|
|
struct rb_node *prev = NULL;
|
|
|
|
struct rb_node *next = NULL;
|
|
|
|
u64 end = range_end(start, len);
|
|
|
|
|
2018-08-22 13:51:52 -06:00
|
|
|
rb_node = __tree_search(&tree->map.rb_root, start, &prev, &next);
|
2007-08-27 14:49:44 -06:00
|
|
|
if (!rb_node) {
|
2011-07-13 21:18:15 -06:00
|
|
|
if (prev)
|
|
|
|
rb_node = prev;
|
|
|
|
else if (next)
|
|
|
|
rb_node = next;
|
|
|
|
else
|
|
|
|
return NULL;
|
2007-08-27 14:49:44 -06:00
|
|
|
}
|
2011-07-13 21:18:15 -06:00
|
|
|
|
2007-08-27 14:49:44 -06:00
|
|
|
em = rb_entry(rb_node, struct extent_map, rb_node);
|
2008-01-24 14:13:08 -07:00
|
|
|
|
2011-07-13 21:18:15 -06:00
|
|
|
if (strict && !(end > em->start && start < extent_map_end(em)))
|
|
|
|
return NULL;
|
2008-01-24 14:13:08 -07:00
|
|
|
|
2017-03-03 01:55:12 -07:00
|
|
|
refcount_inc(&em->refs);
|
2007-08-27 14:49:44 -06:00
|
|
|
return em;
|
|
|
|
}
|
|
|
|
|
2011-07-13 21:18:15 -06:00
|
|
|
/**
|
|
|
|
* lookup_extent_mapping - lookup extent_map
|
|
|
|
* @tree: tree to lookup in
|
|
|
|
* @start: byte offset to start the search
|
|
|
|
* @len: length of the lookup range
|
|
|
|
*
|
|
|
|
* Find and return the first extent_map struct in @tree that intersects the
|
|
|
|
* [start, len] range. There may be additional objects in the tree that
|
|
|
|
* intersect, so check the object returned carefully to make sure that no
|
|
|
|
* additional lookups are needed.
|
|
|
|
*/
|
|
|
|
struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree,
|
|
|
|
u64 start, u64 len)
|
|
|
|
{
|
|
|
|
return __lookup_extent_mapping(tree, start, len, 1);
|
|
|
|
}
|
|
|
|
|
2009-09-18 14:07:03 -06:00
|
|
|
/**
|
|
|
|
* search_extent_mapping - find a nearby extent map
|
|
|
|
* @tree: tree to lookup in
|
|
|
|
* @start: byte offset to start the search
|
|
|
|
* @len: length of the lookup range
|
|
|
|
*
|
|
|
|
* Find and return the first extent_map struct in @tree that intersects the
|
|
|
|
* [start, len] range.
|
|
|
|
*
|
|
|
|
* If one can't be found, any nearby extent may be returned
|
|
|
|
*/
|
|
|
|
struct extent_map *search_extent_mapping(struct extent_map_tree *tree,
|
|
|
|
u64 start, u64 len)
|
|
|
|
{
|
2011-07-13 21:18:15 -06:00
|
|
|
return __lookup_extent_mapping(tree, start, len, 0);
|
2009-09-18 14:07:03 -06:00
|
|
|
}
|
|
|
|
|
2008-06-11 19:52:17 -06:00
|
|
|
/**
|
|
|
|
* remove_extent_mapping - removes an extent_map from the extent tree
|
|
|
|
* @tree: extent tree to remove from
|
2016-03-04 12:23:12 -07:00
|
|
|
* @em: extent map being removed
|
2008-06-11 19:52:17 -06:00
|
|
|
*
|
|
|
|
* Removes @em from @tree. No reference counts are dropped, and no checks
|
|
|
|
* are done to see if the range is in use
|
2007-08-27 14:49:44 -06:00
|
|
|
*/
|
2018-09-12 21:01:15 -06:00
|
|
|
void remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em)
|
2007-08-27 14:49:44 -06:00
|
|
|
{
|
2008-07-18 10:01:11 -06:00
|
|
|
WARN_ON(test_bit(EXTENT_FLAG_PINNED, &em->flags));
|
2018-08-22 13:51:52 -06:00
|
|
|
rb_erase_cached(&em->rb_node, &tree->map);
|
2012-09-14 10:59:20 -06:00
|
|
|
if (!test_bit(EXTENT_FLAG_LOGGING, &em->flags))
|
|
|
|
list_del_init(&em->list);
|
2019-03-27 06:24:12 -06:00
|
|
|
if (test_bit(EXTENT_FLAG_FS_MAPPING, &em->flags))
|
|
|
|
extent_map_device_clear_bits(em, CHUNK_ALLOCATED);
|
2014-02-25 07:15:12 -07:00
|
|
|
RB_CLEAR_NODE(&em->rb_node);
|
2007-08-27 14:49:44 -06:00
|
|
|
}
|
2014-02-25 07:15:13 -07:00
|
|
|
|
|
|
|
void replace_extent_mapping(struct extent_map_tree *tree,
|
|
|
|
struct extent_map *cur,
|
|
|
|
struct extent_map *new,
|
|
|
|
int modified)
|
|
|
|
{
|
|
|
|
WARN_ON(test_bit(EXTENT_FLAG_PINNED, &cur->flags));
|
|
|
|
ASSERT(extent_map_in_tree(cur));
|
|
|
|
if (!test_bit(EXTENT_FLAG_LOGGING, &cur->flags))
|
|
|
|
list_del_init(&cur->list);
|
2018-08-22 13:51:52 -06:00
|
|
|
rb_replace_node_cached(&cur->rb_node, &new->rb_node, &tree->map);
|
2014-02-25 07:15:13 -07:00
|
|
|
RB_CLEAR_NODE(&cur->rb_node);
|
|
|
|
|
|
|
|
setup_extent_mapping(tree, new, modified);
|
|
|
|
}
|
2018-01-05 12:51:11 -07:00
|
|
|
|
|
|
|
static struct extent_map *next_extent_map(struct extent_map *em)
|
|
|
|
{
|
|
|
|
struct rb_node *next;
|
|
|
|
|
|
|
|
next = rb_next(&em->rb_node);
|
|
|
|
if (!next)
|
|
|
|
return NULL;
|
|
|
|
return container_of(next, struct extent_map, rb_node);
|
|
|
|
}
|
|
|
|
|
|
|
|
static struct extent_map *prev_extent_map(struct extent_map *em)
|
|
|
|
{
|
|
|
|
struct rb_node *prev;
|
|
|
|
|
|
|
|
prev = rb_prev(&em->rb_node);
|
|
|
|
if (!prev)
|
|
|
|
return NULL;
|
|
|
|
return container_of(prev, struct extent_map, rb_node);
|
|
|
|
}
|
|
|
|
|
2018-11-28 04:05:13 -07:00
|
|
|
/*
|
|
|
|
* Helper for btrfs_get_extent. Given an existing extent in the tree,
|
2018-01-05 12:51:11 -07:00
|
|
|
* the existing extent is the nearest extent to map_start,
|
|
|
|
* and an extent that you want to insert, deal with overlap and insert
|
|
|
|
* the best fitted new extent into the tree.
|
|
|
|
*/
|
2018-01-05 12:51:17 -07:00
|
|
|
static noinline int merge_extent_mapping(struct extent_map_tree *em_tree,
|
|
|
|
struct extent_map *existing,
|
|
|
|
struct extent_map *em,
|
|
|
|
u64 map_start)
|
2018-01-05 12:51:11 -07:00
|
|
|
{
|
|
|
|
struct extent_map *prev;
|
|
|
|
struct extent_map *next;
|
|
|
|
u64 start;
|
|
|
|
u64 end;
|
|
|
|
u64 start_diff;
|
|
|
|
|
|
|
|
BUG_ON(map_start < em->start || map_start >= extent_map_end(em));
|
|
|
|
|
|
|
|
if (existing->start > map_start) {
|
|
|
|
next = existing;
|
|
|
|
prev = prev_extent_map(next);
|
|
|
|
} else {
|
|
|
|
prev = existing;
|
|
|
|
next = next_extent_map(prev);
|
|
|
|
}
|
|
|
|
|
|
|
|
start = prev ? extent_map_end(prev) : em->start;
|
|
|
|
start = max_t(u64, start, em->start);
|
|
|
|
end = next ? next->start : extent_map_end(em);
|
|
|
|
end = min_t(u64, end, extent_map_end(em));
|
|
|
|
start_diff = start - em->start;
|
|
|
|
em->start = start;
|
|
|
|
em->len = end - start;
|
|
|
|
if (em->block_start < EXTENT_MAP_LAST_BYTE &&
|
|
|
|
!test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
|
|
|
|
em->block_start += start_diff;
|
|
|
|
em->block_len = em->len;
|
|
|
|
}
|
|
|
|
return add_extent_mapping(em_tree, em, 0);
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* btrfs_add_extent_mapping - add extent mapping into em_tree
|
2018-04-03 13:45:57 -06:00
|
|
|
* @fs_info - used for tracepoint
|
2018-01-05 12:51:11 -07:00
|
|
|
* @em_tree - the extent tree into which we want to insert the extent mapping
|
|
|
|
* @em_in - extent we are inserting
|
|
|
|
* @start - start of the logical range btrfs_get_extent() is requesting
|
|
|
|
* @len - length of the logical range btrfs_get_extent() is requesting
|
|
|
|
*
|
|
|
|
* Note that @em_in's range may be different from [start, start+len),
|
|
|
|
* but they must be overlapped.
|
|
|
|
*
|
|
|
|
* Insert @em_in into @em_tree. In case there is an overlapping range, handle
|
|
|
|
* the -EEXIST by either:
|
|
|
|
* a) Returning the existing extent in @em_in if @start is within the
|
|
|
|
* existing em.
|
|
|
|
* b) Merge the existing extent with @em_in passed in.
|
|
|
|
*
|
|
|
|
* Return 0 on success, otherwise -EEXIST.
|
|
|
|
*
|
|
|
|
*/
|
2018-04-03 13:45:57 -06:00
|
|
|
int btrfs_add_extent_mapping(struct btrfs_fs_info *fs_info,
|
|
|
|
struct extent_map_tree *em_tree,
|
2018-01-05 12:51:11 -07:00
|
|
|
struct extent_map **em_in, u64 start, u64 len)
|
|
|
|
{
|
|
|
|
int ret;
|
|
|
|
struct extent_map *em = *em_in;
|
|
|
|
|
|
|
|
ret = add_extent_mapping(em_tree, em, 0);
|
|
|
|
/* it is possible that someone inserted the extent into the tree
|
|
|
|
* while we had the lock dropped. It is also possible that
|
|
|
|
* an overlapping map exists in the tree
|
|
|
|
*/
|
|
|
|
if (ret == -EEXIST) {
|
|
|
|
struct extent_map *existing;
|
|
|
|
|
|
|
|
ret = 0;
|
|
|
|
|
|
|
|
existing = search_extent_mapping(em_tree, start, len);
|
2018-01-05 12:51:16 -07:00
|
|
|
|
2018-04-03 13:45:57 -06:00
|
|
|
trace_btrfs_handle_em_exist(fs_info, existing, em, start, len);
|
2018-01-05 12:51:16 -07:00
|
|
|
|
2018-01-05 12:51:11 -07:00
|
|
|
/*
|
|
|
|
* existing will always be non-NULL, since there must be
|
|
|
|
* extent causing the -EEXIST.
|
|
|
|
*/
|
|
|
|
if (start >= existing->start &&
|
|
|
|
start < extent_map_end(existing)) {
|
|
|
|
free_extent_map(em);
|
|
|
|
*em_in = existing;
|
|
|
|
ret = 0;
|
|
|
|
} else {
|
2018-01-05 12:51:15 -07:00
|
|
|
u64 orig_start = em->start;
|
|
|
|
u64 orig_len = em->len;
|
|
|
|
|
2018-01-05 12:51:11 -07:00
|
|
|
/*
|
|
|
|
* The existing extent map is the one nearest to
|
|
|
|
* the [start, start + len) range which overlaps
|
|
|
|
*/
|
|
|
|
ret = merge_extent_mapping(em_tree, existing,
|
|
|
|
em, start);
|
|
|
|
if (ret) {
|
|
|
|
free_extent_map(em);
|
|
|
|
*em_in = NULL;
|
2018-01-05 12:51:15 -07:00
|
|
|
WARN_ONCE(ret,
|
|
|
|
"unexpected error %d: merge existing(start %llu len %llu) with em(start %llu len %llu)\n",
|
|
|
|
ret, existing->start, existing->len,
|
|
|
|
orig_start, orig_len);
|
2018-01-05 12:51:11 -07:00
|
|
|
}
|
2018-01-05 12:51:15 -07:00
|
|
|
free_extent_map(existing);
|
2018-01-05 12:51:11 -07:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
ASSERT(ret == 0 || ret == -EEXIST);
|
|
|
|
return ret;
|
|
|
|
}
|