linux-stable.git/fs/f2fs/extent_cache.c, branch v6.17

f2fs: Pass a folio to ofs_of_node()

2025-07-22T15:56:53+00:00

All callers now have a folio so pass it in.

Signed-off-by: Matthew Wilcox (Oracle) 
Reviewed-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: Pass a folio to F2FS_INODE()

2025-07-22T15:55:43+00:00

All callers now have a folio, so pass it in.  Also make it const as
F2FS_INODE() does not modify the struct folio passed in (the data it
describes is mutable, but it does not change the contents of the struct).
This may improve code generation.

Signed-off-by: Matthew Wilcox (Oracle) 
Reviewed-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: Pass a folio to sanity_check_extent_cache()

2025-07-22T15:55:31+00:00

The only caller has a folio, so pass it in.

Signed-off-by: Matthew Wilcox (Oracle) 
Reviewed-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: fix KMSAN uninit-value in extent_info usage

2025-06-30T16:43:58+00:00

KMSAN reported a use of uninitialized value in `__is_extent_mergeable()`
 and `__is_back_mergeable()` via the read extent tree path.

The root cause is that `get_read_extent_info()` only initializes three
fields (`fofs`, `blk`, `len`) of `struct extent_info`, leaving the
remaining fields uninitialized. This leads to undefined behavior
when those fields are accessed later, especially during
extent merging.

Fix it by zero-initializing the `extent_info` struct before population.

Reported-by: syzbot+b8c1d60e95df65e827d4@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=b8c1d60e95df65e827d4
Fixes: 94afd6d6e525 ("f2fs: extent cache: support unaligned extent")
Reviewed-by: Chao Yu 
Signed-off-by: Abinash Singh 
Signed-off-by: Jaegeuk Kim

f2fs: Convert dnode_of_data->node_page to node_folio

2025-04-28T15:26:47+00:00

All assignments to this struct member are conversions from a folio
so convert it to be a folio and convert all users.  At the same time,
convert data_blkaddr() to take a folio as all callers now have a folio.
Remove eight calls to compound_head().

Signed-off-by: Matthew Wilcox (Oracle) 
Reviewed-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: Pass a folio to f2fs_init_read_extent_tree()

2025-04-28T15:26:46+00:00

The only caller alredy has a folio so pass it in.  Remove two calls
to compound_head().

Signed-off-by: Matthew Wilcox (Oracle) 
Reviewed-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: add a sysfs node to limit max read extent count per-inode

2024-11-23T15:48:13+00:00

Quoted:
"at this time, there are still 1086911 extent nodes in this zombie
extent tree that need to be cleaned up.

crash_arm64_sprd_v8.0.3++> extent_tree.node_cnt ffffff80896cc500
  node_cnt = {
    counter = 1086911
  },
"

As reported by Xiuhong, there will be a huge number of extent nodes
in extent tree, it may potentially cause:
- slab memory fragments
- extreme long time shrink on extent tree
- low mapping efficiency

Let's add a sysfs node to limit max read extent count for each inode,
by default, value of this threshold is 10240, it can be updated
according to user's requirement.

Reported-by: Xiuhong Wang 
Closes: https://lore.kernel.org/linux-f2fs-devel/20241112110627.1314632-1-xiuhong.wang@unisoc.com/
Signed-off-by: Xiuhong Wang 
Signed-off-by: Zhiguo Niu 
Signed-off-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: fix to shrink read extent node in batches

2024-11-21T16:16:54+00:00

We use rwlock to protect core structure data of extent tree during
its shrink, however, if there is a huge number of extent nodes in
extent tree, during shrink of extent tree, it may hold rwlock for
a very long time, which may trigger kernel hang issue.

This patch fixes to shrink read extent node in batches, so that,
critical region of the rwlock can be shrunk to avoid its extreme
long time hold.

Reported-by: Xiuhong Wang 
Closes: https://lore.kernel.org/linux-f2fs-devel/20241112110627.1314632-1-xiuhong.wang@unisoc.com/
Signed-off-by: Xiuhong Wang 
Signed-off-by: Zhiguo Niu 
Signed-off-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: introduce device aliasing file

2024-11-01T01:19:00+00:00

F2FS should understand how the device aliasing file works and support
deleting the file after use. A device aliasing file can be created by
mkfs.f2fs tool and it can map the whole device with an extent, not
using node blocks. The file space should be pinned and normally used for
read-only usages.

Signed-off-by: Daeho Jeong 
Signed-off-by: Chao Yu 
Reviewed-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: fix several potential integer overflows in file offsets

2024-08-05T20:18:35+00:00

When dealing with large extents and calculating file offsets by
summing up according extent offsets and lengths of unsigned int type,
one may encounter possible integer overflow if the values are
big enough.

Prevent this from happening by expanding one of the addends to
(pgoff_t) type.

Found by Linux Verification Center (linuxtesting.org) with static
analysis tool SVACE.

Fixes: d323d005ac4a ("f2fs: support file defragment")
Cc: stable@vger.kernel.org
Signed-off-by: Nikita Zhandarovich 
Reviewed-by: Chao Yu 
Signed-off-by: Jaegeuk Kim