Currently there're two anonymous inodes (inode and anon_inode in struct
erofs_fscache) for each blob. The former was introduced as the
address_space of page cache for bootstrap.
The latter was initially introduced as both the address_space of page
cache and also a sentinel in the shared domain. Since now the management
of cookies in share domain has been decoupled with the anonymous inode,
there's no need to maintain an extra anonymous inode. Let's unify these
two anonymous inodes.
Besides, in non-share-domain mode only bootstrap will allocate anonymous
inode. To simplify the implementation, always allocate anonymous inode
for both bootstrap and data blobs. Similarly release anonymous inodes
for data blobs when .put_super() is called, or we'll get "VFS: Busy
inodes after unmount." warning.
Also remove the redundant set_nlink() when initializing the anonymous
inode, since i_nlink has already been initialized to 1 when the inode
gets allocated.
Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Jia Zhu <zhujia.zj@bytedance.com>
Link: https://lore.kernel.org/r/20230209063913.46341-5-jefflexu@linux.alibaba.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Relinquish fscache volume with mutex held. Otherwise if a new domain is
registered when the old domain with the same name gets removed from the
list but not relinquished yet, fscache may complain the collision.
Fixes: 8b7adf1dff ("erofs: introduce fscache-based domain")
Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Jia Zhu <zhujia.zj@bytedance.com>
Link: https://lore.kernel.org/r/20230209063913.46341-4-jefflexu@linux.alibaba.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
We'd better not touch sb->s_inodes list and inode->i_count directly.
Let's maintain cookies of share domain in a self-contained list in erofs.
Besides, relinquish cookie with the mutex held. Otherwise if a cookie
is registered when the old cookie with the same name in the same domain
has been removed from the list but not relinquished yet, fscache may
complain "Duplicate cookie detected".
Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Jia Zhu <zhujia.zj@bytedance.com>
Link: https://lore.kernel.org/r/20230209063913.46341-3-jefflexu@linux.alibaba.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Currently metadata is always on bootstrap, and thus device mapping is
not needed so far. Remove the redundant device mapping in the meta
routine.
Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Jia Zhu <zhujia.zj@bytedance.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Link: https://lore.kernel.org/r/20230209063913.46341-2-jefflexu@linux.alibaba.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
For erofs_map_blocks() and erofs_map_blocks_flatmode(), the flags
argument is always EROFS_GET_BLOCKS_RAW. Thus remove the unused flags
parameter for these two functions.
Besides EROFS_GET_BLOCKS_RAW is originally introduced for reading
compressed (raw) data for compressed files. However it's never used
actually and let's remove it now.
Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Yue Hu <huyue2@coolpad.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Link: https://lore.kernel.org/r/20230209024825.17335-2-jefflexu@linux.alibaba.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
- Enable large folios for iomap/fscache mode;
- Avoid sysfs warning due to mounting twice with the same fsid and
domain_id in fscache mode;
- Refine fscache interface among erofs, fscache, and cachefiles;
- Use kmap_local_page() only for metabuf;
- Fixes around crafted images found by syzbot;
- Minor cleanups and documentation updates.
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Merge tag 'erofs-for-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs
Pull erofs updates from Gao Xiang:
"In this cycle, large folios are now enabled in the iomap/fscache mode
for uncompressed files first. In order to do that, we've also cleaned
up better interfaces between erofs and fscache, which are acked by
fscache/netfs folks and included in this pull request.
Other than that, there are random fixes around erofs over fscache and
crafted images by syzbot, minor cleanups and documentation updates.
Summary:
- Enable large folios for iomap/fscache mode
- Avoid sysfs warning due to mounting twice with the same fsid and
domain_id in fscache mode
- Refine fscache interface among erofs, fscache, and cachefiles
- Use kmap_local_page() only for metabuf
- Fixes around crafted images found by syzbot
- Minor cleanups and documentation updates"
* tag 'erofs-for-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs:
erofs: validate the extent length for uncompressed pclusters
erofs: fix missing unmap if z_erofs_get_extent_compressedlen() fails
erofs: Fix pcluster memleak when its block address is zero
erofs: use kmap_local_page() only for erofs_bread()
erofs: enable large folios for fscache mode
erofs: support large folios for fscache mode
erofs: switch to prepare_ondemand_read() in fscache mode
fscache,cachefiles: add prepare_ondemand_read() callback
erofs: clean up cached I/O strategies
erofs: update documentation
erofs: check the uniqueness of fsid in shared domain in advance
erofs: enable large folios for iomap mode
When large folios supported, one folio can be split into several slices,
each of which may be mapped to META/UNMAPPED/MAPPED, and the folio can
be unlocked as a whole only when all slices have completed.
Thus always allocate erofs_fscache_request for each .read_folio() or
.readahead(), in which case the allocated request is responsible for
unlocking folios when all slices have completed.
As described above, each folio or folio range can be mapped into several
slices, while these slices may be mapped to different cookies, and thus
each slice needs its own netfs_cache_resources. Here we introduce
chained requests to support this, where each .read_folio() or
.readahead() calling can correspond to multiple requests. Each request
has its own netfs_cache_resources and thus is used to access one cookie.
Among these requests, there's a primary request, with the others
pointing to the primary request.
Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Jia Zhu <zhujia.zj@bytedance.com>
Link: https://lore.kernel.org/r/20221201074256.16639-2-jefflexu@linux.alibaba.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Switch to prepare_ondemand_read() interface and a self-contained request
completion to get rid of netfs_io_[request|subrequest].
The whole request will still be split into slices (subrequest) according
to the cache state of the backing file. As long as one of the
subrequests fails, the whole request will be marked as failed.
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Jia Zhu <zhujia.zj@bytedance.com>
Link: https://lore.kernel.org/r/20221124034212.81892-3-jefflexu@linux.alibaba.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
When shared domain is enabled, doing mount twice with the same fsid and
domain_id will trigger sysfs warning as shown below:
sysfs: cannot create duplicate filename '/fs/erofs/d0,meta.bin'
CPU: 15 PID: 1051 Comm: mount Not tainted 6.1.0-rc6+ #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)
Call Trace:
<TASK>
dump_stack_lvl+0x38/0x49
dump_stack+0x10/0x12
sysfs_warn_dup.cold+0x17/0x27
sysfs_create_dir_ns+0xb8/0xd0
kobject_add_internal+0xb1/0x240
kobject_init_and_add+0x71/0xa0
erofs_register_sysfs+0x89/0x110
erofs_fc_fill_super+0x98c/0xaf0
vfs_get_super+0x7d/0x100
get_tree_nodev+0x16/0x20
erofs_fc_get_tree+0x20/0x30
vfs_get_tree+0x24/0xb0
path_mount+0x2fa/0xa90
do_mount+0x7c/0xa0
__x64_sys_mount+0x8b/0xe0
do_syscall_64+0x30/0x60
entry_SYSCALL_64_after_hwframe+0x46/0xb0
The reason is erofs_fscache_register_cookie() doesn't guarantee the primary
data blob (aka fsid) is unique in the shared domain and
erofs_register_sysfs() invoked by the second mount will fail due to the
duplicated fsid in the shared domain and report warning.
It would be better to check the uniqueness of fsid before doing
erofs_register_sysfs(), so adding a new flags parameter for
erofs_fscache_register_cookie() and doing the uniqueness check if
EROFS_REG_COOKIE_NEED_NOEXIST is enabled.
After the patch, the error in dmesg for the duplicated mount would be:
erofs: ...: erofs_domain_register_cookie: XX already exists in domain YY
Reviewed-by: Jia Zhu <zhujia.zj@bytedance.com>
Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Hou Tao <houtao1@huawei.com>
Link: https://lore.kernel.org/r/20221125110822.3812942-1-houtao@huaweicloud.com
Fixes: 7d41963759 ("erofs: Support sharing cookies in the same domain")
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
READ/WRITE proved to be actively confusing - the meanings are
"data destination, as used with read(2)" and "data source, as
used with write(2)", but people keep interpreting those as
"we read data from it" and "we write data to it", i.e. exactly
the wrong way.
Call them ITER_DEST and ITER_SOURCE - at least that is harder
to misinterpret...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The xarray iteration only holds the RCU read lock and thus may encounter
XA_RETRY_ENTRY if there's process modifying the xarray concurrently.
This will cause oops when referring to the invalid entry.
Fix this by adding the missing xas_retry(), which will make the
iteration wind back to the root node if XA_RETRY_ENTRY is encountered.
Fixes: d435d53228 ("erofs: change to use asynchronous io for fscache readpage/readahead")
Suggested-by: David Howells <dhowells@redhat.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Reviewed-by: Jia Zhu <zhujia.zj@bytedance.com>
Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Link: https://lore.kernel.org/r/20221114121943.29987-1-jefflexu@linux.alibaba.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
When erofs instance is remounted with fsid or domain_id mount option
specified, the original fsid and domain_id string pointer in sbi->opt
is directly overridden with the fsid and domain_id string in the new
fs_context, without freeing the original fsid and domain_id string.
What's worse, when the new fsid and domain_id string is transferred to
sbi, they are not reset to NULL in fs_context, and thus they are freed
when remount finishes, while sbi is still referring to these strings.
Reconfiguration for fsid and domain_id seems unusual. Thus clarify this
restriction explicitly and dump a warning when users are attempting to
do this.
Besides, to fix the use-after-free issue, move fsid and domain_id from
erofs_mount_opts to outside.
Fixes: c6be2bd0a5 ("erofs: register fscache volume")
Fixes: 8b7adf1dff ("erofs: introduce fscache-based domain")
Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Jia Zhu <zhujia.zj@bytedance.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Link: https://lore.kernel.org/r/20221021023153.1330-1-jefflexu@linux.alibaba.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
For unmapped range, the returned map.m_llen is zero, and thus the
calculated count is unexpected zero.
Prior to the refactoring introduced by commit 1ae9470c3e ("erofs:
clean up .read_folio() and .readahead() in fscache mode"), only the
readahead routine suffers from this. With the refactoring of making
.read_folio() and .readahead() calling one common routine, both
read_folio and readahead have this issue now.
Fix this by calculating count separately in unmapped condition.
Fixes: c665b394b9 ("erofs: implement fscache-based data readahead")
Fixes: 1ae9470c3e ("erofs: clean up .read_folio() and .readahead() in fscache mode")
Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Link: https://lore.kernel.org/r/20221104054028.52208-3-jefflexu@linux.alibaba.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
s_inodes is superblock-specific resource, which should be
protected by sb's specific lock s_inode_list_lock.
Link: https://lore.kernel.org/r/TYCP286MB23238380DE3B74874E8D78ABCA299@TYCP286MB2323.JPNP286.PROD.OUTLOOK.COM
Fixes: 7d41963759 ("erofs: Support sharing cookies in the same domain")
Reviewed-by: Yue Hu <huyue2@coolpad.com>
Reviewed-by: Jia Zhu <zhujia.zj@bytedance.com>
Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Signed-off-by: Dawei Li <set_pte_at@outlook.com>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
The implementation of these two functions in fscache mode is almost the
same. Extract the same part as a generic helper to remove the code
duplication.
Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Jia Zhu <zhujia.zj@bytedance.com>
Link: https://lore.kernel.org/r/20220922062414.20437-1-jefflexu@linux.alibaba.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Several erofs filesystems can belong to one domain, and data blobs can
be shared among these erofs filesystems of same domain.
Users could specify domain_id mount option to create or join into a
domain.
Signed-off-by: Jia Zhu <zhujia.zj@bytedance.com>
Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220918110150.6338-1-zhujia.zj@bytedance.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
A new fscache-based shared domain mode is going to be introduced for
erofs. In which case, same data blobs in same domain will be shared
and reused to reduce on-disk space usage.
The implementation of sharing blobs will be introduced in subsequent
patches.
Signed-off-by: Jia Zhu <zhujia.zj@bytedance.com>
Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220918043456.147-4-zhujia.zj@bytedance.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
If erofs_fscache_alloc_request fail and then goto out, it will return 0.
it should return a negative error code instead of 0.
Fixes: d435d53228 ("erofs: change to use asynchronous io for fscache readpage/readahead")
Signed-off-by: Sun Ke <sunke32@huawei.com>
Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Link: https://lore.kernel.org/r/20220815034829.3940803-1-sunke32@huawei.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
- Leave compressed inodes unsupported in fscache mode for now;
- Avoid crash when using tracepoint cachefiles_prep_read;
- Fix `backmost' behavior due to a recent cleanup;
- Update documentation for better description of recent new features;
- Several decompression cleanups w/o logical change.
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Merge tag 'erofs-for-5.19-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs
Pull more erofs updates from Gao Xiang:
"This is a follow-up to the main updates, including some fixes of
fscache mode related to compressed inodes and a cachefiles tracepoint.
There is also a patch to fix an unexpected decompression strategy
change due to a cleanup in the past. All the fixes are quite small.
Apart from these, documentation is also updated for a better
description of recent new features.
In addition, this has some trivial cleanups without actual code logic
changes, so I could have a more recent codebase to work on folios and
avoiding the PG_error page flag for the next cycle.
Summary:
- Leave compressed inodes unsupported in fscache mode for now
- Avoid crash when using tracepoint cachefiles_prep_read
- Fix `backmost' behavior due to a recent cleanup
- Update documentation for better description of recent new features
- Several decompression cleanups w/o logical change"
* tag 'erofs-for-5.19-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs:
erofs: fix 'backmost' member of z_erofs_decompress_frontend
erofs: simplify z_erofs_pcluster_readmore()
erofs: get rid of label `restart_now'
erofs: get rid of `struct z_erofs_collection'
erofs: update documentation
erofs: fix crash when enable tracepoint cachefiles_prep_read
erofs: leave compressed inodes unsupported in fscache mode for now
- Appoint myself page cache maintainer
- Fix how scsicam uses the page cache
- Use the memalloc_nofs_save() API to replace AOP_FLAG_NOFS
- Remove the AOP flags entirely
- Remove pagecache_write_begin() and pagecache_write_end()
- Documentation updates
- Convert several address_space operations to use folios:
- is_dirty_writeback
- readpage becomes read_folio
- releasepage becomes release_folio
- freepage becomes free_folio
- Change filler_t to require a struct file pointer be the first argument
like ->read_folio
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Merge tag 'folio-5.19' of git://git.infradead.org/users/willy/pagecache
Pull page cache updates from Matthew Wilcox:
- Appoint myself page cache maintainer
- Fix how scsicam uses the page cache
- Use the memalloc_nofs_save() API to replace AOP_FLAG_NOFS
- Remove the AOP flags entirely
- Remove pagecache_write_begin() and pagecache_write_end()
- Documentation updates
- Convert several address_space operations to use folios:
- is_dirty_writeback
- readpage becomes read_folio
- releasepage becomes release_folio
- freepage becomes free_folio
- Change filler_t to require a struct file pointer be the first
argument like ->read_folio
* tag 'folio-5.19' of git://git.infradead.org/users/willy/pagecache: (107 commits)
nilfs2: Fix some kernel-doc comments
Appoint myself page cache maintainer
fs: Remove aops->freepage
secretmem: Convert to free_folio
nfs: Convert to free_folio
orangefs: Convert to free_folio
fs: Add free_folio address space operation
fs: Convert drop_buffers() to use a folio
fs: Change try_to_free_buffers() to take a folio
jbd2: Convert release_buffer_page() to use a folio
jbd2: Convert jbd2_journal_try_to_free_buffers to take a folio
reiserfs: Convert release_buffer_page() to use a folio
fs: Remove last vestiges of releasepage
ubifs: Convert to release_folio
reiserfs: Convert to release_folio
orangefs: Convert to release_folio
ocfs2: Convert to release_folio
nilfs2: Remove comment about releasepage
nfs: Convert to release_folio
jfs: Convert to release_folio
...
Use asynchronous io to read data from fscache may greatly improve IO
bandwidth for sequential buffered read scenario.
Change erofs_fscache_read_folios to erofs_fscache_read_folios_async,
and read data from fscache asynchronously.
Make .readpage()/.readahead() to use this new helper.
Signed-off-by: Xin Yin <yinxin.x@bytedance.com>
Reviewed-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220509074028.74954-23-jefflexu@linux.alibaba.com
Acked-by: Chao Yu <chao@kernel.org>
[ Gao Xiang: minor styling changes. ]
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Implement the data plane of reading data from data blobs over fscache
for inline layout.
For the heading non-inline part, the data plane for non-inline layout is
reused, while only the tail packing part needs special handling.
Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220425122143.56815-20-jefflexu@linux.alibaba.com
Acked-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Implement the data plane of reading data from data blobs over fscache
for non-inline layout.
Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220425122143.56815-19-jefflexu@linux.alibaba.com
Acked-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Add erofs_fscache_read_folios() helper reading from fscache. It supports
on-demand read semantics. That is, it will make the backend prepare for
the data when cache miss. Once data ready, it will read from the cache.
This helper can then be used to implement .readpage()/.readahead() of
on-demand read semantics.
Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220425122143.56815-15-jefflexu@linux.alibaba.com
Acked-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Introduce one anonymous inode for data blobs so that erofs can cache
metadata directly within such anonymous inode.
Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220425122143.56815-14-jefflexu@linux.alibaba.com
Acked-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Introduce a context structure for managing data blobs, and helper
functions for initializing and cleaning up this context structure.
Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220425122143.56815-13-jefflexu@linux.alibaba.com
Acked-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
A new fscache based mode is going to be introduced for erofs, in which
case on-demand read semantics is implemented through fscache.
As the first step, register fscache volume for each erofs filesystem.
That means, data blobs can not be shared among erofs filesystems. In the
following iteration, we are going to introduce the domain semantics, in
which case several erofs filesystems can belong to one domain, and data
blobs can be shared among these erofs filesystems of one domain.
Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220425122143.56815-12-jefflexu@linux.alibaba.com
Acked-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>