[BUG]
Test case btrfs/002 would fail if larger folios are enabled for
metadata:
assertion failed: folio, in fs/btrfs/extent_io.c:4358
------------[ cut here ]------------
kernel BUG at fs/btrfs/extent_io.c:4358!
invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
CPU: 1 PID: 30916 Comm: fsstress Tainted: G OE 6.7.0-rc3-custom+ #128
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS unknown 2/2/2022
RIP: 0010:assert_eb_folio_uptodate+0x98/0xe0 [btrfs]
Call Trace:
<TASK>
extent_buffer_test_bit+0x3c/0x70 [btrfs]
free_space_test_bit+0xcd/0x140 [btrfs]
modify_free_space_bitmap+0x27a/0x430 [btrfs]
add_to_free_space_tree+0x8d/0x160 [btrfs]
__btrfs_free_extent.isra.0+0xef1/0x13c0 [btrfs]
__btrfs_run_delayed_refs+0x786/0x13c0 [btrfs]
btrfs_run_delayed_refs+0x33/0x120 [btrfs]
btrfs_commit_transaction+0xa2/0x1350 [btrfs]
iterate_supers+0x77/0xe0
ksys_sync+0x60/0xa0
__do_sys_sync+0xa/0x20
do_syscall_64+0x3f/0xf0
entry_SYSCALL_64_after_hwframe+0x6e/0x76
</TASK>
[CAUSE]
The function extent_buffer_test_bit() is not folio compatible.
It still assumes the old fixed page size, when an extent buffer with
large folio passed in, only eb->folios[0] is populated.
Then if the target bit range falls in the 2nd page of the folio, then we
would check eb->folios[1], and trigger the ASSERT().
[FIX]
Just migrate eb_bitmap_offset() to folio interfaces, using the
folio_size() to replace PAGE_SIZE.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
If we still go the old page based iterator functions, like
bio_for_each_segment_all(), we can hit middle pages of a folio (compound
page).
In that case if we set any page flag on those middle pages, we can
easily trigger VM_BUG_ON(), as for compound page flags, they should
follow their flag policies (normally only set on leading or tail pages).
To avoid such problem in the future full folio migration, here we do:
- Change from bio_for_each_segment_all() to bio_for_each_folio_all()
This completely removes the ability to access the middle page.
- Add extra ASSERT()s for data read/write paths
To ensure we only get single paged folio for data now.
- Rename those end io functions to follow a certain schema
* end_bbio_compressed_read()
* end_bbio_compressed_write()
These two endio functions don't set any page flags, as they use pages
not mapped to any address space.
They can be very good candidates for higher order folio testing.
And they are shared between compression and encoded IO.
* end_bbio_data_read()
* end_bbio_data_write()
* end_bbio_meta_read()
* end_bbio_meta_write()
The old function names are not unified:
- end_bio_extent_writepage()
- end_bio_extent_readpage()
- extent_buffer_write_end_io()
- extent_buffer_read_end_io()
They share no schema on where the "end_*io" string should be, nor can
be confusing just using "extent_buffer" and "extent" to distinguish
data and metadata paths.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Although subpage itself is conflicting with higher folio, since subpage
(sectorsize < PAGE_SIZE and nodesize < PAGE_SIZE) means we will never
need higher order folio, there is a hidden pitfall:
- btrfs_page_*() helpers
Those helpers are an abstraction to handle both subpage and non-subpage
cases, which means we're going to pass pages pointers to those helpers.
And since those helpers are shared between data and metadata paths, it's
unavoidable to let them to handle folios, including higher order
folios).
Meanwhile for true subpage case, we should only have a single page
backed folios anyway, thus add a new ASSERT() for btrfs_subpage_assert()
to ensure that.
Also since those helpers are shared between both data and metadata, add
some extra ASSERT()s for data path to make sure we only get single page
backed folio for now.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
These two functions are still using the old page based code, which is
not going to handle larger folios at all.
The migration itself is going to involve the following changes:
- PAGE_SIZE -> folio_size()
- PAGE_SHIFT -> folio_shift()
- get_eb_page_index() -> get_eb_folio_index()
- get_eb_offset_in_page() -> get_eb_offset_in_folio()
And since we're going to support larger folios, although above straight
conversion is good enough, this patch would add extra comments in the
involved functions to explain why the same single line code can now
cover 3 cases:
- folio_size == PAGE_SIZE, sectorsize == PAGE_SIZE, nodesize >= PAGE_SIZE
The common, non-subpage case with per-page folio.
- folio_size > PAGE_SIZE, sectorsize == PAGE_SIZE, nodesize >= PAGE_SIZE
The incoming larger folio, non-subpage case.
- folio_size == PAGE_SIZE, sectorsize < PAGE_SIZE, nodesize < PAGE_SIZE
The existing subpage case, we won't larger folio anyway.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This fixes as case in "btrfs: refactor alloc_extent_buffer() to
allocate-then-attach method".
We have been seeing panics in the CI for the subpage stuff recently, it
happens on btrfs/187 but could potentially happen anywhere.
In the subpage case, if we race with somebody else inserting the same
extent buffer, the error case will end up calling
detach_extent_buffer_page() on the page twice.
This is done first in the bit
for (int i = 0; i < attached; i++)
detach_extent_buffer_page(eb, eb->pages[i];
and then again in btrfs_release_extent_buffer().
This works fine for !subpage because we're the only person who ever has
ourselves on the private, and so when we do the initial
detach_extent_buffer_page() we know we've completely removed it.
However for subpage we could be using this page private elsewhere, so
this results in a double put on the subpage, which can result in an
early freeing.
The fix here is to clear eb->pages[i] for everything we detach. Then
anything still attached to the eb is freed in
btrfs_release_extent_buffer().
Because of this change we must update
btrfs_release_extent_buffer_pages() to not use num_extent_folios,
because it assumes eb->folio[0] is set properly. Since this is only
interested in freeing any pages we have on the extent buffer we can
simply use INLINE_EXTENT_BUFFER_PAGES.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Although we have migrated extent_buffer::pages[] to folios[], we're
still mostly using the folio_page() help to grab the page.
This patch would do the following cleanups for metadata:
- Introduce num_extent_folios() helper
This is to replace most num_extent_pages() callers.
- Use num_extent_folios() to iterate future large folios
This allows us to use things like
bio_add_folio()/bio_add_folio_nofail(), and only set the needed flags
for the folio (aka the leading/tailing page), which reduces the loop
iteration to 1 for large folios.
- Change metadata related functions to use folio pointers
Including their function name, involving:
* attach_extent_buffer_page()
* detach_extent_buffer_page()
* page_range_has_eb()
* btrfs_release_extent_buffer_pages()
* btree_clear_page_dirty()
* btrfs_page_inc_eb_refs()
* btrfs_page_dec_eb_refs()
- Change btrfs_is_subpage() to accept an address_space pointer
This is to allow both page->mapping and folio->mapping to be utilized.
As data is still using the old per-page code, and may keep so for a
while.
- Special corner case place holder for future order mismatches between
extent buffer and inode filemap
For now it's just a block of comments and a dead ASSERT(), no real
handling yet.
The subpage code would still go page, just because subpage and large
folio are conflicting conditions, thus we don't need to bother subpage
with higher order folios at all. Just folio_page(folio, 0) would be
enough.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor styling tweaks ]
Signed-off-by: David Sterba <dsterba@suse.com>
For now extent_buffer::pages[] are still only accepting single page
pointer, thus we can migrate to folios pretty easily.
As for single page, page and folio are 1:1 mapped, including their page
flags.
This patch would just do the conversion from struct page to struct
folio, providing the first step to higher order folio in the future.
This conversion is pretty simple:
- extent_buffer::pages[] -> extent_buffer::folios[]
- page_address(eb->pages[i]) -> folio_address(eb->pages[i])
- eb->pages[i] -> folio_page(eb->folios[i], 0)
There would be more specific cleanups preparing for the incoming higher
order folio support.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently alloc_extent_buffer() utilizes find_or_create_page() to
allocate one page a time for an extent buffer.
This method has the following disadvantages:
- find_or_create_page() is the legacy way of allocating new pages
With the new folio infrastructure, find_or_create_page() is just
redirected to filemap_get_folio().
- Lacks the way to support higher order (order >= 1) folios
As we can not yet let filemap give us a higher order folio.
This patch would change the workflow by the following way:
Old | new
-----------------------------------+-------------------------------------
| ret = btrfs_alloc_page_array();
for (i = 0; i < num_pages; i++) { | for (i = 0; i < num_pages; i++) {
p = find_or_create_page(); | ret = filemap_add_folio();
/* Attach page private */ | /* Reuse page cache if needed */
/* Reused eb if needed */ |
| /* Attach page private and
| reuse eb if needed */
| }
By this we split the page allocation and private attaching into two
parts, allowing future updates to each part more easily, and migrate to
folio interfaces (especially for possible higher order folios).
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The value set as scrub_speed_max accepts size with suffixes
(k/m/g/t/p/e) but we should still validate it for trailing characters,
similar to what we do with chunk_size_store.
CC: stable@vger.kernel.org # 5.15+
Signed-off-by: David Disseldorp <ddiss@suse.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The radix-tree has been superseded by the xarray
(https://lwn.net/Articles/745073), this patch converts the
btrfs_root::delayed_nodes, the APIs are used in a simple way.
First idea is to do xa_insert() but this would require GFP_ATOMIC
allocation which we want to avoid if possible. The preload mechanism of
radix-tree can be emulated within the xarray API.
- xa_reserve() with GFP_NOFS outside of the lock, the reserved entry
is inserted atomically at most once
- xa_store() under a lock, in case something races in we can detect that
and xa_load() returns a valid pointer
All uses of xa_load() must check for a valid pointer in case they manage
to get between the xa_reserve() and xa_store(), this is handled in
btrfs_get_delayed_node().
Otherwise the functionality is equivalent, xarray implements the
radix-tree and there should be no performance difference.
The patch continues the efforts started in 253bf57555 ("btrfs: turn
delayed_nodes_tree into an XArray") and fixes the problems with locking
and GFP flags 088aea3b97 ("Revert "btrfs: turn delayed_nodes_tree
into an XArray"").
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The definition for btrfs_get_extent() is using "u64 end" as the last
parameter, but in implementation we go "u64 len", and all call sites
follows the implementation.
This can be very confusing during development, as most developers
including me, would just use the snippet returned by LSP (clangd in my
case), which would only check the definition.
Unfortunately this mismatch is introduced from the very beginning of
btrfs.
Fix it to prevent further confusion.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently, in struct extent_map, we use an unsigned int (32 bits) to
identify the compression type of an extent and an unsigned long (64 bits
on a 64 bits platform, 32 bits otherwise) for flags. We are only using
6 different flags, so an unsigned long is excessive and we can use flags
to identify the compression type instead of using a dedicated 32 bits
field.
We can easily have tens or hundreds of thousands (or more) of extent maps
on busy and large filesystems, specially with compression enabled or many
or large files with tons of small extents. So it's convenient to have the
extent_map structure as small as possible in order to use less memory.
So remove the compression type field from struct extent_map, use flags
to identify the compression type and shorten the flags field from an
unsigned long to a u32. This saves 8 bytes (on 64 bits platforms) and
reduces the size of the structure from 136 bytes down to 128 bytes, using
now only two cache lines, and increases the number of extent maps we can
have per 4K page from 30 to 32. By using a u32 for the flags instead of
an unsigned long, we no longer use test_bit(), set_bit() and clear_bit(),
but that level of atomicity is not needed as most flags are never cleared
once set (before adding an extent map to the tree), and the ones that can
be cleared or set after an extent map is added to the tree, are always
performed while holding the write lock on the extent map tree, while the
reader holds a lock on the tree or tests for a flag that never changes
once the extent map is in the tree (such as compression flags).
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
At mergable_maps() instead of having a single if statement with many
ORed and ANDed conditions, refactor it with multiple if statements that
check a single condition and return immediately once a requirement fails.
This makes it easier to read.
Also change the return type from int to bool, make the arguments const
and rename the function from mergable_maps() to mergeable_maps().
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The extent map pointer argument for extent_map_end() can be const as we
are not modifyng anything in the extent map. So make it const, as it will
allow further changes to callers that have a const extent map pointer.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When trying to merge an extent map that was just inserted or unpinned, we
will try to merge it with any adjacent extent map that is suitable.
However we will only check if our extent map is mergeable after searching
for the previous and next extent maps in the rbtree, meaning that we are
doing unnecessary calls to rb_prev() and rb_next() in case our extent map
is not mergeable (it's compressed, in the list of modifed extents, being
logged or pinned), wasting CPU time chasing rbtree pointers and pulling
in unnecessary cache lines.
So change the logic to check first if an extent map is mergeable before
searching for the next and previous extent maps in the rbtree.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
At unpin_extent_range() we trigger a WARN_ON() when we don't find an
extent map or we find one with a start offset not matching the start
offset of the target range. This however isn't very useful for debugging
because:
1) We don't know which condition was triggered, as they are both in the
same WARN_ON() call;
2) We don't know which inode was affected, from which root, for which
range, what's the start offset of the extent map, and so on.
So trigger a separate warning for each case and log a message for each
case providing information about the inode, its root, the target range,
the generation and the start offset of the extent map we found.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
At btrfs_add_extent_mapping(), in case add_extent_mapping() returned
-EEXIST, it's pointless to assign 0 to 'ret' since we will assign a value
to it shortly after, without 'ret' being used before that. So remove that
pointless assignment.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There's no need to export add_extent_mapping(), as it's only used inside
extent_map.c and in the self tests. For the tests we can use instead
btrfs_add_extent_mapping(), which will accomplish exactly the same as we
don't expect collisions in any of them. So unexport it and make the tests
use btrfs_add_extent_mapping() instead of add_extent_mapping().
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Some error messages of the extent map tests print decimal values of start
offsets and lengths, while other are oddly printing in hexadecimal, which
is far less human friendly, specially taking into consideration that all
the values are small and multiples of 4K, so it's a lot easier to read
them as decimal values. Change the format specifiers to print as decimal
instead.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Several of the extent map tests call btrfs_add_extent_mapping() which is
supposed to succeed and return an extent map through the pointer to
pointer argument. However the tests are deliberately ignoring a NULL
extent map, which is not expected to happen. So change the tests to error
out if a NULL extent map is found.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In test case 4 for extent maps, if we error out we are supposed to print
in interval but instead of printing a non-inclusive end offset, we are
printing the length of the interval, which makes it confusing. So fix
that to print the exclusive end offset instead.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When setting up a new extent map, at setup_extent_mapping(), we're doing
a list move operation to add the extent map the tree's list of modified
extents. This is confusing because at this point the extent map can not
be in any list, because it's a new extent map. So replace the list move
with a list add and add an assertion that checks that the extent map is
not currently in any list.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The file_extent_tree was added in 41a2ee75aa ("btrfs: introduce
per-inode file extent tree") so we have an explicit mapping of the file
extents to know where it is safe to update i_size. When the feature
NO_HOLES is enabled, and it's been a mkfs default since 5.15, the tree
is not necessary.
To save some space in the inode, allocate the tree only when necessary.
This reduces size by 16 bytes from 1096 to 1080 on a x86_64 release
config.
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When profiling a workload I noticed we were constantly calling getxattr.
These were mostly coming from __remove_privs, which will lookup if
security.capability exists to remove it. However instrumenting getxattr
showed we get called nearly constantly on an idle machine on a lot of
accesses.
These are wasteful and not free. Other security LSMs have a way to
cache their results, but capability doesn't have this, so it's asking us
all the time for the xattr.
Fix this by setting a flag in our inode that it doesn't have a
security.capability xattr. We set this on new inodes and after a failed
lookup of security.capability. If we set this xattr at all we'll clear
the flag.
I haven't found a test in fsperf that this makes a visible difference
on, but I assume fs_mark related tests would show it clearly. This is a
perf report output of the smallfiles100k run where it shows 20% of our
time spent in __remove_privs because we're looking up the non-existent
xattr.
--21.86%--btrfs_write_check.constprop.0
--21.62%--__file_remove_privs
--21.55%--security_inode_need_killpriv
--21.54%--cap_inode_need_killpriv
--21.53%--__vfs_getxattr
--20.89%--btrfs_getxattr
Obviously this is just CPU time in a mostly IO bound test, so the actual
effect of removing this callchain is minimal. However in just normal
testing of an idle system tracing showed around 100 getxattr calls per
minute, and with this patch there are 0.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We've deprecated these a while ago in 5.11, go ahead and remove the code
for them.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Acked-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We're currently setting this when we try to load the roots and we see
that usebackuproot is set. Instead set this at mount option parsing
time.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Acked-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There's no reason this has to happen in open_ctree, and in fact in the
old mount API we had to call this from remount. Move this to super.c,
unexport it, and call it from both mount and reconfigure.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Acked-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that we've switched to the new mount API, remove the old stuff.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Acked-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We add these mount options based on the fs_devices settings, which can
be set once we've opened the fs_devices. Move these into their own
helper and call it from get_tree_super.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Acked-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that we have all of the parts in place to use the new mount API,
switch our fs_type to use the new callbacks.
There are a few things that have to be done at the same time because of
the order of operations changes that come along with the new mount API.
These must be done in the same patch otherwise things will go wrong.
1. Export and use btrfs_check_options in open_ctree(). This is because
the options are done ahead of time, and we need to check them once we
have the feature flags loaded.
2. Update the free space cache settings. Since we're coming in with the
options already set we need to make sure we don't undo what the user
has asked for.
3. Set our sb_flags at init_fs_context time, the fs_context stuff is
trying to manage the sb_flagss itself, so move that into
init_fs_context and out of the fill super part.
Additionally I've marked the unused functions with __maybe_unused and
will remove them in a future patch.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Acked-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This is a special case that we've carried around since 0723a0473f ("btrfs:
allow mounting btrfs subvolumes with different ro/rw options") where
we'll under the covers flip the file system to RW if you're mixing and
matching ro/rw options with different subvol mounts. The first mount is
what the super gets setup as, so we'd handle this by remount the super
as rw under the covers to facilitate this behavior.
With the new mount API we can't really allow this, because user space
has the ability to specify the super block settings, and the mount
settings. So if the user explicitly sets the super block as read only,
and then tried to mount a rw mount with the super block we'll reject
this. However the old API was less descriptive and thus we allowed this
kind of behavior.
This patch preserves this behavior for the old API calls. This is
inspired by Christians work [1], and includes his comment in
btrfs_get_tree_super() explaining the history and how it all works in
the old and new APIs.
Link: https://lore.kernel.org/all/20230626-fs-btrfs-mount-api-v1-2-045e9735a00b@kernel.org/
Reviewed-by: Christian Brauner <brauner@kernel.org>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This is the actual mounting callback for the new mount API. Implement
this using our current fill super as a guideline, making the appropriate
adjustments for the new mount API.
Our old mount operation had two fs_types, one to handle the actual
opening, and the one that we called to handle the actual opening and
then did the subvol lookup for returning the actual root dentry. This
is mirrored here, but simply with different behaviors for ->get_tree.
We use the existence of ->s_fs_info to tell which part we're in. The
initial call allocates the fs_info, then call mount_fc() with a
duplicated fc to do the actual open_ctree part. Then we take that
vfsmount and use it to look up our subvolume that we're mounting and
return that as our s_root. This idea was taken from Christians attempt
to convert us to the new mount API [1].
In btrfs_get_tree_super() the mount device is scanned and opened in one
go under uuid_mutex we expect that all related devices have been already
scanned, either by mount or from the outside. A device forget can be
called on some of the devices as the whole context is not protected but
it's an unlikely event, though it's a minor behaviour change.
References: https://lore.kernel.org/all/20230626-fs-btrfs-mount-api-v1-2-045e9735a00b@kernel.org/
Reviewed-by: Christian Brauner <brauner@kernel.org>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add note about device scanning ]
Signed-off-by: David Sterba <dsterba@suse.com>
This is what is used to remount the file system with the new mount API.
Because the mount options are parsed separately and one at a time I've
added a helper to emit the mount options after the fact once the mount
is configured, this matches the dmesg output for what happens with the
old mount API.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Acked-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We are going to use the fs context to hold the mount options, so
allocate the btrfs_fs_context when we're asked to init the fs context,
and free it in the free callback.
Reviewed-by: Christian Brauner <brauner@kernel.org>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The parse_param callback handles one parameter at a time, take our
existing mount option parsing loop and adjust it to handle one parameter
at a time, and tie it into the fs_context_operations.
Create a btrfs_fs_context object that will store the various mount
properties, we'll house this in fc->fs_private. This is necessary to
separate because remounting will use ->reconfigure, and we'll get a new
copy of the parsed parameters, so we can no longer directly mess with
the fs_info in this stage.
In the future we'll add this to the btrfs_fs_info and update the users
to use the new context object instead.
There's a change how the option device= is processed. Previously all
mount options were parsed in one go under uuid_mutex and the devices
opened. This prevented a concurrent scan to happen during mount. Now we
could see a device scan happen (e.g. by udev) but this should not affect
the end result, mount will either see the populated fs_devices or will
scan the device by itself.
Alternatively we could save all the device paths first and then process
them in one go as before but this does not seem to be necessary.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Acked-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add note about device scanning ]
Signed-off-by: David Sterba <dsterba@suse.com>
In order to convert to the new mount API we have to change how we do the
mount option parsing. For now we're going to duplicate these helpers to
make it easier to follow, and then remove the old code once everything
is in place. This patch contains the re-definition of all of our mount
options into the new fs_parameter_spec format.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Acked-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
With the old mount API we'd pre-populate the mount options with the
space cache settings of the file system, and then the user toggled them
on or off with the mount options. When we switch to the new mount API
the mount options will be set before we get into opening the file
system, so we need a flag to indicate that the user explicitly asked for
-o nospace_cache so we can make the appropriate changes after the fact.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Acked-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When we remount ro->rw or rw->ro we have some cleanup tasks that have to
be managed. Split these out into their own function to make
btrfs_remount smaller.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Acked-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We currently don't allow these options to be set if we're extent tree v2
via the mount option parsing. However when we switch to the new mount
API we'll no longer have the super block loaded, so won't be able to
make this distinction at mount option parsing time. Address this by
checking for extent tree v2 at the point where we make the decision to
rebuild the free space tree.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Acked-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently we pre-load the space cache settings in btrfs_parse_options,
however when we switch to the new mount API the mount option parsing
will happen before we have the super block loaded. Add a helper to set
the appropriate options based on the fs settings, this will allow us to
have consistent free space cache settings.
This also folds in the space cache related decisions we make for subpage
sectorsize support, so all of this is done in one place.
Since this was being called by parse options it looks like we're
changing the behavior of remount, but in fact we aren't. The
pre-loading of the free space cache settings is done because we want to
handle the case of users not using any space_cache options, we'll derive
the appropriate mount option based on the on disk state. On remount
this wouldn't reset anything as we'll have cleared the v1 cache
generation if we mounted -o nospace_cache. Similarly it's impossible to
turn off the free space tree without specifically saying -o
nospace_cache,clear_cache, which will delete the free space tree and
clear the compat_ro option. Again in this case calling this code in
remount wouldn't result in any change.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Acked-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
With the new mount API we'll be setting our compression well before we
call open_ctree. We don't want to overwrite our settings, so set the
default in btrfs_init_fs_info instead of open_ctree.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Acked-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We're going to need to validate mount options after they're all parsed
with the new mount API, split this code out into its own helper so we
can use it when we swap over to the new mount API.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Acked-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor adjustments in the messages ]
Signed-off-by: David Sterba <dsterba@suse.com>
We already communicate to filesystems when a remount request comes from
the old mount API as some filesystems choose to implement different
behavior in the new mount API than the old mount API to e.g., take the
chance to fix significant API bugs. Allow the same for regular mount
requests.
Fixes: b330966f79 ("fuse: reject options on reconfigure via fsconfig(2)")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
After commit ac3c0d36a2 ("btrfs: make fiemap more efficient and accurate
reporting extent sharedness") we no longer need to create special extent
maps during fiemap that have a block start with the EXTENT_MAP_DELALLOC
value. So this block start value for extent maps is no longer used since
then, therefore remove it.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently btrfs extent buffer helpers are doing all the cross-page
handling, as there is no guarantee that all those eb pages are
contiguous.
However on systems with enough memory, there is a very high chance the
page cache for btree_inode are allocated with physically contiguous
pages.
In that case, we can skip all the complex cross-page handling, thus
speeding up the code.
This patch adds a new member, extent_buffer::addr, which is only set to
non-NULL if all the extent buffer pages are physically contiguous.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Reflow btrfs_free_tree_block() so that there is one level of indentation
needed.
This patch has no functional changes.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Use memset_page() in memset_extent_buffer() instead of opencoding it.
This does not not change any functionality.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that we're not clearing the dirty flag off of extent_buffers in zoned mode,
all that is left of btrfs_redirty_list_add() is a memzero() and some
ASSERT()ions.
As we're also memzero()ing the buffer on write-out btrfs_redirty_list_add()
has become obsolete and can be removed.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
One a zoned filesystem, never clear the dirty flag of an extent buffer,
but instead mark it as zeroout.
On writeout, when encountering a marked extent_buffer, zero it out.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
