linux.git/fs/erofs/data.c, branch v6.16

erofs: address D-cache aliasing

2025-07-10T09:08:27+00:00

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

erofs: fix to add missing tracepoint in erofs_read_folio()

2025-07-10T09:08:26+00:00

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

erofs: fix to add missing tracepoint in erofs_readahead()

2025-07-10T09:08:25+00:00

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

erofs: add 'fsoffset' mount option to specify filesystem offset

2025-05-22T03:57:57+00:00

When attempting to use an archive file, such as APEX on android,
as a file-backed mount source, it fails because EROFS image within
the archive file does not start at offset 0. As a result, a loop
or a dm device is still needed to attach the image file at an
appropriate offset first. Similarly, if an EROFS image within a
block device does not start at offset 0, it cannot be mounted
directly either.

To address this issue, this patch adds a new mount option `fsoffset=x'
to accept a start offset for the primary device. The offset should be
aligned to the block size. EROFS will add this offset before performing
read requests.

Signed-off-by: Sheng Yong 
Signed-off-by: Wang Shuai 
Reviewed-by: Gao Xiang 
Link: https://lore.kernel.org/r/20250517090544.2687651-1-shengyong1@xiaomi.com
[ Gao Xiang: minor update on documentation and the error message. ]
Reviewed-by: Hongbo Li 
Signed-off-by: Gao Xiang

erofs: implement 48-bit block addressing for unencoded inodes

2025-03-16T17:25:26+00:00

It adapts the on-disk changes from the previous commit.  It also
supports EROFS_NULL_ADDR (all 1's) for EROFS_INODE_FLAT_PLAIN inodes
to indicate 0-filled inodes, as it's common for composefs use cases.
As a result, EROFS_INODE_CHUNK_BASED is no longer needed.

Signed-off-by: Gao Xiang 
Acked-by: Chao Yu 
Link: https://lore.kernel.org/r/20250310095459.2620647-5-hsiangkao@linux.alibaba.com

erofs: add 48-bit block addressing on-disk support

2025-03-16T17:23:25+00:00

The current 32-bit block addressing limits EROFS to a 16TiB maximum
volume size with 4KiB blocks.  However, several new use cases now
require larger capacity support:
 - Massive datasets for model training in order to boost random
   sampling performance for each epoch;

 - Object storage clients using EROFS direct passthrough.

This extends core on-disk structures to support 48-bit block addressing,
such as inodes, device slots, and inode chunks.

Additionally:
 - Expand superblock root NID to 8-byte `rootnid_8b` to enable full
   out-of-place update incremental builds;

 - Introduce `epoch` field in the superblock as well as add `mtime`
   field to 32-byte compact inodes for basic timestamp support.

Signed-off-by: Gao Xiang 
Acked-by: Chao Yu 
Link: https://lore.kernel.org/r/20250310095459.2620647-4-hsiangkao@linux.alibaba.com

erofs: get rid of erofs_map_blocks_flatmode()

2025-03-16T17:23:25+00:00

It's simple enough to be folded into erofs_map_blocks().

Signed-off-by: Gao Xiang 
Acked-by: Chao Yu 
Link: https://lore.kernel.org/r/20250310095459.2620647-2-hsiangkao@linux.alibaba.com

erofs: get rid of erofs_kmap_type

2025-03-16T17:21:24+00:00

Since EROFS_KMAP_ATOMIC is no longer valid, get rid of erofs_kmap_type too.

Signed-off-by: Bo Liu 
Reviewed-by: Gao Xiang 
Reviewed-by: Chao Yu 
Link: https://lore.kernel.org/r/20250217093141.2659-1-liubo03@inspur.com
Signed-off-by: Gao Xiang

erofs: reference `struct erofs_device_info` for erofs_map_dev

2024-12-16T13:02:06+00:00

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

erofs: use `struct erofs_device_info` for the primary device

2024-12-16T13:01:59+00:00

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