kernel/linux.git/fs/erofs/data.c, branch v6.12.80

erofs: fix to add missing tracepoint in erofs_readahead()

2025-07-17T16:37:18+00:00

[ Upstream commit d53238b614e01266a3d36b417b60a502e0698504 ] Commit 771c994ea51f ("erofs: convert all uncompressed cases to iomap") converts to use iomap interface, it removed trace_erofs_readahead() tracepoint in the meantime, let's add it back. Fixes: 771c994ea51f ("erofs: convert all uncompressed cases to iomap") Signed-off-by: Chao Yu Reviewed-by: Gao Xiang Link: https://lore.kernel.org/r/20250707084832.2725677-1-chao@kernel.org Signed-off-by: Gao Xiang Signed-off-by: Sasha Levin

erofs: address D-cache aliasing

2025-07-17T16:37:15+00:00

commit 27917e8194f91dffd8b4825350c63cb68e98ce58 upstream. Flush the D-cache before unlocking folios for compressed inodes, as they are dirtied during decompression. Avoid calling flush_dcache_folio() on every CPU write, since it's more like playing whack-a-mole without real benefit. It has no impact on x86 and arm64/risc-v: on x86, flush_dcache_folio() is a no-op, and on arm64/risc-v, PG_dcache_clean (PG_arch_1) is clear for new page cache folios. However, certain ARM boards are affected, as reported. Fixes: 3883a79abd02 ("staging: erofs: introduce VLE decompression support") Closes: https://lore.kernel.org/r/c1e51e16-6cc6-49d0-a63e-4e9ff6c4dd53@pengutronix.de Closes: https://lore.kernel.org/r/38d43fae-1182-4155-9c5b-ffc7382d9917@siemens.com Tested-by: Jan Kiszka Tested-by: Stefan Kerkmann Signed-off-by: Gao Xiang Link: https://lore.kernel.org/r/20250709034614.2780117-2-hsiangkao@linux.alibaba.com Signed-off-by: Greg Kroah-Hartman

erofs: fix to add missing tracepoint in erofs_read_folio()

2025-07-17T16:37:15+00:00

commit 99f7619a77a0a2e3e2bcae676d0f301769167754 upstream. Commit 771c994ea51f ("erofs: convert all uncompressed cases to iomap") converts to use iomap interface, it removed trace_erofs_readpage() tracepoint in the meantime, let's add it back. Fixes: 771c994ea51f ("erofs: convert all uncompressed cases to iomap") Signed-off-by: Chao Yu Reviewed-by: Gao Xiang Link: https://lore.kernel.org/r/20250708111942.3120926-1-chao@kernel.org Signed-off-by: Gao Xiang Signed-off-by: Greg Kroah-Hartman

erofs: reference `struct erofs_device_info` for erofs_map_dev

2024-12-27T13:02:00+00:00

[ Upstream commit f8d920a402aec3482931cb5f1539ed438740fc49 ] Record `m_sb` and `m_dif` to replace `m_fscache`, `m_daxdev`, `m_fp` and `m_dax_part_off` in order to simplify the codebase. Note that `m_bdev` is still left since it can be assigned from `sb->s_bdev` directly. Reviewed-by: Chao Yu Signed-off-by: Gao Xiang Link: https://lore.kernel.org/r/20241212235401.2857246-1-hsiangkao@linux.alibaba.com Stable-dep-of: 6422cde1b0d5 ("erofs: use buffered I/O for file-backed mounts by default") Signed-off-by: Sasha Levin

erofs: use `struct erofs_device_info` for the primary device

2024-12-27T13:02:00+00:00

[ Upstream commit 7b00af2c5414dc01e0718deef7ead81102867636 ] Instead of just listing each one directly in `struct erofs_sb_info` except that we still use `sb->s_bdev` for the primary block device. Reviewed-by: Chao Yu Signed-off-by: Gao Xiang Link: https://lore.kernel.org/r/20241216125310.930933-2-hsiangkao@linux.alibaba.com Stable-dep-of: 6422cde1b0d5 ("erofs: use buffered I/O for file-backed mounts by default") Signed-off-by: Sasha Levin

erofs: fix file-backed mounts over FUSE

2024-12-05T13:02:00+00:00

[ Upstream commit 3a23787ca8756920d65fda39f41353a4be1d1642 ] syzbot reported a null-ptr-deref in fuse_read_args_fill: fuse_read_folio+0xb0/0x100 fs/fuse/file.c:905 filemap_read_folio+0xc6/0x2a0 mm/filemap.c:2367 do_read_cache_folio+0x263/0x5c0 mm/filemap.c:3825 read_mapping_folio include/linux/pagemap.h:1011 [inline] erofs_bread+0x34d/0x7e0 fs/erofs/data.c:41 erofs_read_superblock fs/erofs/super.c:281 [inline] erofs_fc_fill_super+0x2b9/0x2500 fs/erofs/super.c:625 Unlike most filesystems, some network filesystems and FUSE need unavoidable valid `file` pointers for their read I/Os [1]. Anyway, those use cases need to be supported too. [1] https://docs.kernel.org/filesystems/vfs.html Reported-by: syzbot+0b1279812c46e48bb0c1@syzkaller.appspotmail.com Closes: https://lore.kernel.org/r/6727bbdf.050a0220.3c8d68.0a7e.GAE@google.com Fixes: fb176750266a ("erofs: add file-backed mount support") Tested-by: syzbot+0b1279812c46e48bb0c1@syzkaller.appspotmail.com Signed-off-by: Gao Xiang Link: https://lore.kernel.org/r/20241114234905.1873723-1-hsiangkao@linux.alibaba.com Signed-off-by: Sasha Levin

erofs: simplify erofs_map_blocks_flatmode()

2024-09-10T07:27:14+00:00

Get rid of redundant variables (nblocks, offset) and a dead branch (!tailendpacking). Signed-off-by: Hongzhen Luo Reviewed-by: Gao Xiang Reviewed-by: Chao Yu Link: https://lore.kernel.org/r/20240905030339.1474396-1-hongzhen@linux.alibaba.com Signed-off-by: Gao Xiang

erofs: support unencoded inodes for fileio

2024-09-10T07:26:36+00:00

Since EROFS only needs to handle read requests in simple contexts, Just directly use vfs_iocb_iter_read() for data I/Os. Reviewed-by: Sandeep Dhavale Reviewed-by: Chao Yu Signed-off-by: Gao Xiang Link: https://lore.kernel.org/r/20240905093031.2745929-1-hsiangkao@linux.alibaba.com

erofs: add file-backed mount support

2024-09-10T07:26:35+00:00

It actually has been around for years: For containers and other sandbox use cases, there will be thousands (and even more) of authenticated (sub)images running on the same host, unlike OS images. Of course, all scenarios can use the same EROFS on-disk format, but bdev-backed mounts just work well for OS images since golden data is dumped into real block devices. However, it's somewhat hard for container runtimes to manage and isolate so many unnecessary virtual block devices safely and efficiently [1]: they just look like a burden to orchestrators and file-backed mounts are preferred indeed. There were already enough attempts such as Incremental FS, the original ComposeFS and PuzzleFS acting in the same way for immutable fses. As for current EROFS users, ComposeFS, containerd and Android APEXs will be directly benefited from it. On the other hand, previous experimental feature "erofs over fscache" was once also intended to provide a similar solution (inspired by Incremental FS discussion [2]), but the following facts show file-backed mounts will be a better approach: - Fscache infrastructure has recently been moved into new Netfslib which is an unexpected dependency to EROFS really, although it originally claims "it could be used for caching other things such as ISO9660 filesystems too." [3] - It takes an unexpectedly long time to upstream Fscache/Cachefiles enhancements. For example, the failover feature took more than one year, and the deamonless feature is still far behind now; - Ongoing HSM "fanotify pre-content hooks" [4] together with this will perfectly supersede "erofs over fscache" in a simpler way since developers (mainly containerd folks) could leverage their existing caching mechanism entirely in userspace instead of strictly following the predefined in-kernel caching tree hierarchy. After "fanotify pre-content hooks" lands upstream to provide the same functionality, "erofs over fscache" will be removed then (as an EROFS internal improvement and EROFS will not have to bother with on-demand fetching and/or caching improvements anymore.) [1] https://github.com/containers/storage/pull/2039 [2] https://lore.kernel.org/r/CAOQ4uxjbVxnubaPjVaGYiSwoGDTdpWbB=w_AeM6YM=zVixsUfQ@mail.gmail.com [3] https://docs.kernel.org/filesystems/caching/fscache.html [4] https://lore.kernel.org/r/cover.1723670362.git.josef@toxicpanda.com Closes: https://github.com/containers/composefs/issues/144 Reviewed-by: Sandeep Dhavale Reviewed-by: Chao Yu Signed-off-by: Gao Xiang Link: https://lore.kernel.org/r/20240830032840.3783206-1-hsiangkao@linux.alibaba.com

erofs: support multi-page folios for erofs_bread()

2024-07-26T10:47:57+00:00

If the requested page is part of the previous multi-page folio, there is no need to call read_mapping_folio() again. Also, get rid of the remaining one of page->index [1] in our codebase. [1] https://lore.kernel.org/r/Zp8fgUSIBGQ1TN0D@casper.infradead.org Cc: Matthew Wilcox Reviewed-by: Chao Yu Signed-off-by: Gao Xiang Link: https://lore.kernel.org/r/20240723073024.875290-1-hsiangkao@linux.alibaba.com