- refine the filesystem overview for better description of recent
new features like FSDAX and Fscache;
- add the new `fsid' mount option;
- fix some typos.
Link: https://lore.kernel.org/r/20220527070133.77962-1-hsiangkao@linux.alibaba.com
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
EROFS images should inherit modification time rather than change time,
since users and host tooling have no easy way to control change time.
To reflect the new timestamp meaning, i_ctime and i_ctime_nsec are
renamed to i_mtime and i_mtime_nsec.
Link: https://lore.kernel.org/r/20220311041829.3109511-1-dvander@google.com # v1
Signed-off-by: David Anderson <dvander@google.com>
[ Gao Xiang: update document as well. ]
Reviewed-by: Chao Yu <chao@kernel.org>
Link: https://lore.kernel.org/r/20220317114959.106787-1-hsiangkao@linux.alibaba.com # v2
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
In order to support multi-layer container images, add multiple
device feature to EROFS. Two ways are available to use for now:
- Devices can be mapped into 32-bit global block address space;
- Device ID can be specified with the chunk indexes format.
Note that it assumes no extent would cross device boundary and mkfs
should take care of it seriously.
In the future, a dedicated device manager could be introduced then
thus extra devices can be automatically scanned by UUID as well.
Link: https://lore.kernel.org/r/20211014081010.43485-1-hsiangkao@linux.alibaba.com
Reviewed-by: Chao Yu <chao@kernel.org>
Reviewed-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Currently, uncompressed data except for tail-packing inline is
consecutive on disk.
In order to support chunk-based data deduplication, add a new
corresponding inode data layout.
In the future, the data source of chunks can be either (un)compressed.
Link: https://lore.kernel.org/r/20210820100019.208490-1-hsiangkao@linux.alibaba.com
Reviewed-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
DAX is quite useful for some VM use cases in order to save guest
memory extremely with minimal lightweight EROFS.
In order to prepare for such use cases, add preliminary dax support
for non-tailpacking regular files for now.
Tested with the DRAM-emulated PMEM and the EROFS image generated by
"mkfs.erofs -Enoinline_data enwik9.fsdax.img enwik9"
Link: https://lore.kernel.org/r/20210805003601.183063-3-hsiangkao@linux.alibaba.com
Cc: nvdimm@lists.linux.dev
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>