kernel/linux.git/fs/squashfs/super.c, branch v6.4

Merge tag 'fs.idmapped.squashfs.v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/idmapping

2022-12-13T04:24:51+00:00

Pull squashfs update from Seth Forshee: "This is a simple patch to enable idmapped mounts for squashfs. All functionality squashfs needs to support idmapped mounts is already implemented in generic VFS code, so all that is needed is to set FS_ALLOW_IDMAP in fs_flags" * tag 'fs.idmapped.squashfs.v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/idmapping: squashfs: enable idmapped mounts

squashfs: fix null-ptr-deref in squashfs_fill_super

2022-11-18T21:55:09+00:00

When squashfs_read_table() returns an error or `sb->s_magic != SQUASHFS_MAGIC`, enters the error branch and calls msblk->thread_ops->destroy(msblk) to destroy msblk. However, msblk->thread_ops has not been initialized. Therefore, the following problem is triggered: ================================================================== BUG: KASAN: null-ptr-deref in squashfs_fill_super+0xe7a/0x13b0 Read of size 8 at addr 0000000000000008 by task swapper/0/1 CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.1.0-rc3-next-20221031 #367 Call Trace: dump_stack_lvl+0x73/0x9f print_report+0x743/0x759 kasan_report+0xc0/0x120 __asan_load8+0xd3/0x140 squashfs_fill_super+0xe7a/0x13b0 get_tree_bdev+0x27b/0x450 squashfs_get_tree+0x19/0x30 vfs_get_tree+0x49/0x150 path_mount+0xaae/0x1350 init_mount+0xad/0x100 do_mount_root+0xbc/0x1d0 mount_block_root+0x173/0x316 mount_root+0x223/0x236 prepare_namespace+0x1eb/0x237 kernel_init_freeable+0x528/0x576 kernel_init+0x29/0x250 ret_from_fork+0x1f/0x30 ================================================================== To solve this issue, msblk->thread_ops is initialized immediately after msblk is assigned a value. Link: https://lkml.kernel.org/r/20221101073343.3961562-1-libaokun1@huawei.com Fixes: b0645770d3c7 ("squashfs: add the mount parameter theads=") Signed-off-by: Baokun Li Reviewed-by: Xiaoming Ni Reviewed-by: Phillip Lougher Cc: Yu Kuai Cc: Zhang Yi Signed-off-by: Andrew Morton

squashfs: allows users to configure the number of decompression threads

2022-11-18T21:55:08+00:00

The maximum number of threads in the decompressor_multi.c file is fixed and cannot be adjusted according to user needs. Therefore, the mount parameter needs to be added to allow users to configure the number of threads as required. The upper limit is num_online_cpus() * 2. Link: https://lkml.kernel.org/r/20221019030930.130456-3-nixiaoming@huawei.com Signed-off-by: Xiaoming Ni Reviewed-by: Phillip Lougher Cc: Jianguo Chen Cc: Jubin Zhong Cc: Zhang Yi Signed-off-by: Andrew Morton

squashfs: add the mount parameter theads=

2022-11-18T21:55:08+00:00

Patch series 'squashfs: Add the mount parameter "threads="'. Currently, Squashfs supports multiple decompressor parallel modes. However, this mode can be configured only during kernel building and does not support flexible selection during runtime. In the current patch set, the mount parameter "threads=" is added to allow users to select the parallel decompressor mode and configure the number of decompressors when mounting a file system. "threads=" The upper limit is num_online_cpus() * 2. This patch (of 2): Squashfs supports three decompression concurrency modes: Single-thread mode: concurrent reads are blocked and the memory overhead is small. Multi-thread mode/percpu mode: reduces concurrent read blocking but increases memory overhead. The corresponding schema must be fixed at compile time. During mounting, the concurrent decompression mode cannot be adjusted based on file read blocking. The mount parameter theads= is added to select the concurrent decompression mode of a single SquashFS file system image. Link: https://lkml.kernel.org/r/20221019030930.130456-1-nixiaoming@huawei.com Link: https://lkml.kernel.org/r/20221019030930.130456-2-nixiaoming@huawei.com Signed-off-by: Xiaoming Ni Reviewed-by: Phillip Lougher Cc: Jianguo Chen Cc: Jubin Zhong Cc: Zhang Yi Signed-off-by: Andrew Morton

squashfs: enable idmapped mounts

2022-11-07T09:24:22+00:00

For squashfs all needed functionality for idmapped mounts is already implemented by the generic handlers in the VFS. Thus, it is sufficient to just enable the corresponding FS_ALLOW_IDMAP flag to support idmapped mounts. We use this for unprivileged (user namespaced) containers based on squashfs images as rootfs in GyroidOS. A simple test using the mount-idmapped tool executed as user with uid=1000 looks as follows: $ mkdir test $ echo "test" > test/test_file $ mksquashfs test/ fs.img $ sudo mkdir /mnt/test $ sudo mkdir /mnt/mapped $ sudo mount fs.img -o loop /mnt/test/ $ sudo ./mount-idmapped --map-mount b:1000:2000:1 /mnt/test/ /mnt/mapped/ $ mount | tail -n2 fs.img on /mnt/test type squashfs (ro,relatime,errors=continue) fs.img on /mnt/mapped type squashfs (ro,relatime,idmapped,errors=continue) $ ls -lan /mnt/test/ total 5 drwxr-xr-x 2 1000 1000 32 Okt 24 13:36 . drwxr-xr-x 6 0 0 4096 Okt 24 13:38 .. -rw-r--r-- 1 1000 1000 5 Okt 24 13:36 test_file $ ls -lan /mnt/mapped/ total 5 drwxr-xr-x 2 2000 2000 32 Okt 24 13:36 . drwxr-xr-x 6 0 0 4096 Okt 24 13:38 .. -rw-r--r-- 1 2000 2000 5 Okt 24 13:36 test_file Signed-off-by: Michael Weiß Reviewed-by: Christian Brauner Reviewed-by: Phillip Lougher Signed-off-by: Christian Brauner (Microsoft)

Revert "squashfs: provide backing_dev_info in order to disable read-ahead"

2022-07-30T01:12:34+00:00

Patch series "Implement readahead for squashfs", v7. Commit 9eec1d897139("squashfs: provide backing_dev_info in order to disable read-ahead") mitigates the performance drop issue for squashfs by closing readahead for it. This series implements readahead callback for squashfs. This patch (of 4): This reverts 9eec1d897139e5 ("squashfs: provide backing_dev_info in order to disable read-ahead"). Revert closing the readahead to squashfs since the readahead callback for squashfs is implemented. Link: https://lkml.kernel.org/r/20220617083810.337573-1-hsinyi@chromium.org Link: https://lkml.kernel.org/r/20220617083810.337573-2-hsinyi@chromium.org Signed-off-by: Hsin-Yi Wang Suggested-by: Xiongwei Song Cc: Phillip Lougher Cc: Matthew Wilcox Cc: Marek Szyprowski Cc: Zheng Liang Cc: Zhang Yi Cc: Hou Tao Cc: Miao Xie Cc: kernel test robot Signed-off-by: Andrew Morton

squashfs: Convert squashfs to read_folio

2022-05-09T20:21:46+00:00

This is a "weak" conversion which converts straight back to using pages. A full conversion should be performed at some point, hopefully by someone familiar with the filesystem. Signed-off-by: Matthew Wilcox (Oracle)

fs: allocate inode by using alloc_inode_sb()

2022-03-22T22:57:03+00:00

The inode allocation is supposed to use alloc_inode_sb(), so convert kmem_cache_alloc() of all filesystems to alloc_inode_sb(). Link: https://lkml.kernel.org/r/20220228122126.37293-5-songmuchun@bytedance.com Signed-off-by: Muchun Song Acked-by: Theodore Ts'o [ext4] Acked-by: Roman Gushchin Cc: Alex Shi Cc: Anna Schumaker Cc: Chao Yu Cc: Dave Chinner Cc: Fam Zheng Cc: Jaegeuk Kim Cc: Johannes Weiner Cc: Kari Argillander Cc: Matthew Wilcox (Oracle) Cc: Michal Hocko Cc: Qi Zheng Cc: Shakeel Butt Cc: Trond Myklebust Cc: Vladimir Davydov Cc: Vlastimil Babka Cc: Wei Yang Cc: Xiongchun Duan Cc: Yang Shi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

squashfs: provide backing_dev_info in order to disable read-ahead

2022-01-15T14:30:24+00:00

Commit c1f6925e1091 ("mm: put readahead pages in cache earlier") causes the read performance of squashfs to deteriorate.Through testing, we find that the performance will be back by closing the readahead of squashfs. So we want to learn the way of ubifs, provides backing_dev_info and disable read-ahead We tested the following data by fio. squashfs image blocksize=128K test command: fio --name basic --bs=? --filename="/mnt/test_file" --rw=? --iodepth=1 --ioengine=psync --runtime=200 --time_based turn on squashfs readahead in 5.10 kernel bs(k) read/randread MB/s 4 randread 271 128 randread 231 1024 randread 246 4 read 310 128 read 245 1024 read 247 turn off squashfs readahead in 5.10 kernel bs(k) read/randread MB/s 4 randread 293 128 randread 330 1024 randread 363 4 read 338 128 read 360 1024 read 365 turn on squashfs readahead and revert the commit c1f6925e1091("mm: put readahead pages in cache earlier") in 5.10 kernel bs(k) read/randread MB/s 4 randread 289 128 randread 306 1024 randread 335 4 read 337 128 read 336 1024 read 338 Link: https://lkml.kernel.org/r/20211116113141.1391026-1-zhengliang6@huawei.com Signed-off-by: Zheng Liang Reviewed-by: Phillip Lougher Cc: Zhang Yi Cc: Hou Tao Cc: Miao Xie Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

squashfs: use bdev_nr_bytes instead of open coding it

2021-10-18T20:43:23+00:00

Use the proper helper to read the block device size. Signed-off-by: Christoph Hellwig Reviewed-by: Kees Cook Acked-by: Phillip Lougher Link: https://lore.kernel.org/r/20211018101130.1838532-24-hch@lst.de Signed-off-by: Jens Axboe