user/sven/linux.git/fs/cachefiles, branch stable/6.2.y

fscache,cachefiles: add prepare_ondemand_read() callback

2022-12-07T02:56:29Z

Add prepare_ondemand_read() callback dedicated for the on-demand read scenario, so that callers from this scenario can be decoupled from netfs_io_subrequest. The original cachefiles_prepare_read() is now refactored to a generic routine accepting a parameter list instead of netfs_io_subrequest. There's no logic change, except that the debug id of subrequest and request is removed from trace_cachefiles_prep_read(). Reviewed-by: Jeff Layton Signed-off-by: Jingbo Xu Acked-by: David Howells Link: https://lore.kernel.org/r/20221124034212.81892-2-jefflexu@linux.alibaba.com Signed-off-by: Gao Xiang

cachefiles: use vfs_tmpfile_open() helper

2022-09-24T05:00:00Z

Use the vfs_tmpfile_open() helper instead of doing tmpfile creation and opening separately. The only minor difference is that previously no permission checking was done, while vfs_tmpfile_open() will call may_open() with zero access mask (i.e. no access is checked). Even if this would make a difference with callers caps (don't see how it could, even in the LSM codepaths) cachfiles raises caps before performing the tmpfile creation, so this extra permission check will not result in any regression. Reviewed-by: Christian Brauner (Microsoft) Signed-off-by: Miklos Szeredi

cachefiles: only pass inode to *mark_inode_inuse() helpers

2022-09-24T04:59:59Z

The only reason to pass dentry was because of a pr_notice() text. Move that to the two callers where it makes sense and add a WARN_ON() to the third. file_inode(file) is never NULL on an opened file. Remove check in cachefiles_unmark_inode_in_use(). Do not open code cachefiles_do_unmark_inode_in_use() in cachefiles_put_directory(). Signed-off-by: Miklos Szeredi

cachefiles: tmpfile error handling cleanup

2022-09-24T04:59:59Z

Separate the error labels from the success path and use 'ret' to store the error value before jumping to the error label. Signed-off-by: Miklos Szeredi

cachefiles: make on-demand request distribution fairer

2022-08-31T15:41:10Z

For now, enqueuing and dequeuing on-demand requests all start from idx 0, this makes request distribution unfair. In the weighty concurrent I/O scenario, the request stored in higher idx will starve. Searching requests cyclically in cachefiles_ondemand_daemon_read, makes distribution fairer. Fixes: c8383054506c ("cachefiles: notify the user daemon when looking up cookie") Reported-by: Yongqing Li Signed-off-by: Xin Yin Signed-off-by: David Howells Reviewed-by: Jeffle Xu Reviewed-by: Gao Xiang Link: https://lore.kernel.org/r/20220817065200.11543-1-yinxin.x@bytedance.com/ # v1 Link: https://lore.kernel.org/r/20220825020945.2293-1-yinxin.x@bytedance.com/ # v2

cachefiles: fix error return code in cachefiles_ondemand_copen()

2022-08-31T15:41:10Z

The cache_size field of copen is specified by the user daemon. If cache_size < 0, then the OPEN request is expected to fail, while copen itself shall succeed. However, returning 0 is indeed unexpected when cache_size is an invalid error code. Fix this by returning error when cache_size is an invalid error code. Changes ======= v4: update the code suggested by Dan v3: update the commit log suggested by Jingbo. Fixes: c8383054506c ("cachefiles: notify the user daemon when looking up cookie") Signed-off-by: Sun Ke Suggested-by: Jeffle Xu Suggested-by: Dan Carpenter Signed-off-by: David Howells Reviewed-by: Gao Xiang Reviewed-by: Jingbo Xu Reviewed-by: Dan Carpenter Link: https://lore.kernel.org/r/20220818111935.1683062-1-sunke32@huawei.com/ # v2 Link: https://lore.kernel.org/r/20220818125038.2247720-1-sunke32@huawei.com/ # v3 Link: https://lore.kernel.org/r/20220826023515.3437469-1-sunke32@huawei.com/ # v4

cachefiles: narrow the scope of flushed requests when releasing fd

2022-07-05T15:12:21Z

When an anonymous fd is released, only flush the requests associated with it, rather than all of requests in xarray. Fixes: 9032b6e8589f ("cachefiles: implement on-demand read") Signed-off-by: Jia Zhu Signed-off-by: David Howells Reviewed-by: Jeffle Xu Reviewed-by: Gao Xiang Link: https://listman.redhat.com/archives/linux-cachefs/2022-June/006937.html

cachefiles: add tracepoints for on-demand read mode

2022-05-17T16:11:18Z

Add tracepoints for on-demand read mode. Currently following tracepoints are added: OPEN request / COPEN reply CLOSE request READ request / CREAD reply write through anonymous fd release of anonymous fd Signed-off-by: Jeffle Xu Acked-by: David Howells Link: https://lore.kernel.org/r/20220425122143.56815-8-jefflexu@linux.alibaba.com Signed-off-by: Gao Xiang

cachefiles: enable on-demand read mode

2022-05-17T16:11:18Z

Enable on-demand read mode by adding an optional parameter to the "bind" command. On-demand mode will be turned on when this parameter is "ondemand", i.e. "bind ondemand". Otherwise cachefiles will work in the original mode. Signed-off-by: Jeffle Xu Link: https://lore.kernel.org/r/20220509074028.74954-7-jefflexu@linux.alibaba.com Acked-by: David Howells Signed-off-by: Gao Xiang

cachefiles: implement on-demand read

2022-05-17T16:11:18Z

Implement the data plane of on-demand read mode. The early implementation [1] place the entry to cachefiles_ondemand_read() in fscache_read(). However, fscache_read() can only detect if the requested file range is fully cache miss, whilst we need to notify the user daemon as long as there's a hole inside the requested file range. Thus the entry is now placed in cachefiles_prepare_read(). When working in on-demand read mode, once a hole detected, the read routine will send a READ request to the user daemon. The user daemon needs to fetch the data and write it to the cache file. After sending the READ request, the read routine will hang there, until the READ request is handled by the user daemon. Then it will retry to read from the same file range. If no progress encountered, the read routine will fail then. A new NETFS_SREQ_ONDEMAND flag is introduced to indicate that on-demand read should be done when a cache miss encountered. [1] https://lore.kernel.org/all/20220406075612.60298-6-jefflexu@linux.alibaba.com/ #v8 Signed-off-by: Jeffle Xu Acked-by: David Howells Link: https://lore.kernel.org/r/20220425122143.56815-6-jefflexu@linux.alibaba.com Signed-off-by: Gao Xiang