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* Merge tag 'vfs-6.8.netfs' of ↵Linus Torvalds2024-01-191-13/+21
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs Pull netfs updates from Christian Brauner: "This extends the netfs helper library that network filesystems can use to replace their own implementations. Both afs and 9p are ported. cifs is ready as well but the patches are way bigger and will be routed separately once this is merged. That will remove lots of code as well. The overal goal is to get high-level I/O and knowledge of the page cache and ouf of the filesystem drivers. This includes knowledge about the existence of pages and folios The pull request converts afs and 9p. This removes about 800 lines of code from afs and 300 from 9p. For 9p it is now possible to do writes in larger than a page chunks. Additionally, multipage folio support can be turned on for 9p. Separate patches exist for cifs removing another 2000+ lines. I've included detailed information in the individual pulls I took. Summary: - Add NFS-style (and Ceph-style) locking around DIO vs buffered I/O calls to prevent these from happening at the same time. - Support for direct and unbuffered I/O. - Support for write-through caching in the page cache. - O_*SYNC and RWF_*SYNC writes use write-through rather than writing to the page cache and then flushing afterwards. - Support for write-streaming. - Support for write grouping. - Skip reads for which the server could only return zeros or EOF. - The fscache module is now part of the netfs library and the corresponding maintainer entry is updated. - Some helpers from the fscache subsystem are renamed to mark them as belonging to the netfs library. - Follow-up fixes for the netfs library. - Follow-up fixes for the 9p conversion" * tag 'vfs-6.8.netfs' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs: (50 commits) netfs: Fix wrong #ifdef hiding wait cachefiles: Fix signed/unsigned mixup netfs: Fix the loop that unmarks folios after writing to the cache netfs: Fix interaction between write-streaming and cachefiles culling netfs: Count DIO writes netfs: Mark netfs_unbuffered_write_iter_locked() static netfs: Fix proc/fs/fscache symlink to point to "netfs" not "../netfs" netfs: Rearrange netfs_io_subrequest to put request pointer first 9p: Use length of data written to the server in preference to error 9p: Do a couple of cleanups 9p: Fix initialisation of netfs_inode for 9p cachefiles: Fix __cachefiles_prepare_write() 9p: Use netfslib read/write_iter afs: Use the netfs write helpers netfs: Export the netfs_sreq tracepoint netfs: Optimise away reads above the point at which there can be no data netfs: Implement a write-through caching option netfs: Provide a launder_folio implementation netfs: Provide a writepages implementation netfs, cachefiles: Pass upper bound length to allow expansion ...
| * cachefiles: Fix signed/unsigned mixupDavid Howells2024-01-091-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In __cachefiles_prepare_write(), the start and pos variables were made unsigned 64-bit so that the casts in the checking could be got rid of - which should be fine since absolute file offsets can't be negative, except that an error code may be obtained from vfs_llseek(), which *would* be negative. This breaks the error check. Fix this for now by reverting pos and start to be signed and putting back the casts. Unfortunately, the error value checks cannot be replaced with IS_ERR_VALUE() as long might be 32-bits. Fixes: 7097c96411d2 ("cachefiles: Fix __cachefiles_prepare_write()") Reported-by: Simon Horman <horms@kernel.org> Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202401071152.DbKqMQMu-lkp@intel.com/ Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Simon Horman <horms@kernel.org> Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> cc: Yiqun Leng <yqleng@linux.alibaba.com> cc: Jia Zhu <zhujia.zj@bytedance.com> cc: Jeff Layton <jlayton@kernel.org> cc: linux-cachefs@redhat.com cc: linux-erofs@lists.ozlabs.org cc: linux-fsdevel@vger.kernel.org cc: linux-mm@kvack.org
| * netfs: Fix interaction between write-streaming and cachefiles cullingDavid Howells2024-01-051-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | An issue can occur between write-streaming (storing dirty data in partial non-uptodate pages) and a cachefiles object being culled to make space. The problem occurs because the cache object is only marked in use while there are files open using it. Once it has been released, it can be culled and the cookie marked disabled. At this point, a streaming write is permitted to occur (if the cache is active, we require pages to be prefetched and cached), but the cache can become active again before this gets flushed out - and then two effects can occur: (1) The cache may be asked to write out a region that's less than its DIO block size (assumed by cachefiles to be PAGE_SIZE) - and this causes one of two debugging statements to be emitted. (2) netfs_how_to_modify() gets confused because it sees a page that isn't allowed to be non-uptodate being uptodate and tries to prefetch it - leading to a warning that PG_fscache is set twice. Fix this by the following means: (1) Add a netfs_inode flag to disallow write-streaming to an inode and set it if we ever do local caching of that inode. It remains set for the lifetime of that inode - even if the cookie becomes disabled. (2) If the no-write-streaming flag is set, then make netfs_how_to_modify() always want to prefetch instead. (3) If netfs_how_to_modify() decides it wants to prefetch a folio, but that folio has write-streamed data in it, then it requires the folio be flushed first. (4) Export a counter of the number of times we wanted to prefetch a non-uptodate page, but found it had write-streamed data in it. (5) Export a counter of the number of times we cancelled a write to the cache because it didn't DIO align and remove the debug statements. Reported-by: Marc Dionne <marc.dionne@auristor.com> Signed-off-by: David Howells <dhowells@redhat.com> cc: Jeff Layton <jlayton@kernel.org> cc: linux-cachefs@redhat.com cc: linux-erofs@lists.ozlabs.org cc: linux-fsdevel@vger.kernel.org cc: linux-mm@kvack.org
| * cachefiles: Fix __cachefiles_prepare_write()David Howells2024-01-031-11/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix __cachefiles_prepare_write() to correctly determine whether the requested write will fit correctly with the DIO alignment. Reported-by: Gao Xiang <hsiangkao@linux.alibaba.com> Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: Yiqun Leng <yqleng@linux.alibaba.com> Tested-by: Jia Zhu <zhujia.zj@bytedance.com> cc: Jeff Layton <jlayton@kernel.org> cc: linux-cachefs@redhat.com cc: linux-erofs@lists.ozlabs.org cc: linux-fsdevel@vger.kernel.org cc: linux-mm@kvack.org
| * netfs, cachefiles: Pass upper bound length to allow expansionDavid Howells2023-12-281-4/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Make netfslib pass the maximum length to the ->prepare_write() op to tell the cache how much it can expand the length of a write to. This allows a write to the server at the end of a file to be limited to a few bytes whilst writing an entire block to the cache (something required by direct I/O). Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> cc: linux-cachefs@redhat.com cc: linux-fsdevel@vger.kernel.org cc: linux-mm@kvack.org
* | fs: move kiocb_start_write() into vfs_iocb_iter_write()Amir Goldstein2023-11-241-3/+2
|/ | | | | | | | | | | | | | | | | | | | | | | | In vfs code, sb_start_write() is usually called after the permission hook in rw_verify_area(). vfs_iocb_iter_write() is an exception to this rule, where kiocb_start_write() is called by its callers. Move kiocb_start_write() from the callers into vfs_iocb_iter_write() after the rw_verify_area() checks, to make them "start-write-safe". The semantics of vfs_iocb_iter_write() is changed, so that the caller is responsible for calling kiocb_end_write() on completion only if async iocb was queued. The completion handlers of both callers were adapted to this semantic change. This is needed for fanotify "pre content" events. Suggested-by: Jan Kara <jack@suse.cz> Suggested-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Link: https://lore.kernel.org/r/20231122122715.2561213-14-amir73il@gmail.com Reviewed-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org>
* cachefiles: use kiocb_{start,end}_write() helpersAmir Goldstein2023-08-211-13/+3
| | | | | | | | | | | Use helpers instead of the open coded dance to silence lockdep warnings. Suggested-by: Jan Kara <jack@suse.cz> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Jens Axboe <axboe@kernel.dk> Message-Id: <20230817141337.1025891-8-amir73il@gmail.com> Signed-off-by: Christian Brauner <brauner@kernel.org>
* fscache,cachefiles: add prepare_ondemand_read() callbackJingbo Xu2022-12-071-27/+50
| | | | | | | | | | | | | | | | | 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 <jlayton@kernel.org> Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com> Acked-by: David Howells <dhowells@redhat.com> Link: https://lore.kernel.org/r/20221124034212.81892-2-jefflexu@linux.alibaba.com Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
* cachefiles: implement on-demand readJeffle Xu2022-05-181-2/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 <jefflexu@linux.alibaba.com> Acked-by: David Howells <dhowells@redhat.com> Link: https://lore.kernel.org/r/20220425122143.56815-6-jefflexu@linux.alibaba.com Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
* cachefiles: extract write routineJeffle Xu2022-05-181-26/+35
| | | | | | | | | | | | | | | | | | | Extract the generic routine of writing data to cache files, and make it generally available. This will be used by the following patch implementing on-demand read mode. Since it's called inside CacheFiles module, make the interface generic and unrelated to netfs_cache_resources. It is worth noting that, ki->inval_counter is not initialized after this cleanup. It shall not make any visible difference, since inval_counter is no longer used in the write completion routine, i.e. cachefiles_write_complete(). Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com> Acked-by: David Howells <dhowells@redhat.com> Link: https://lore.kernel.org/r/20220425122143.56815-2-jefflexu@linux.alibaba.com Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
* Merge tag 'netfs-prep-20220318' of ↵Linus Torvalds2022-03-311-5/+5
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs Pull netfs updates from David Howells: "Netfs prep for write helpers. Having had a go at implementing write helpers and content encryption support in netfslib, it seems that the netfs_read_{,sub}request structs and the equivalent write request structs were almost the same and so should be merged, thereby requiring only one set of alloc/get/put functions and a common set of tracepoints. Merging the structs also has the advantage that if a bounce buffer is added to the request struct, a read operation can be performed to fill the bounce buffer, the contents of the buffer can be modified and then a write operation can be performed on it to send the data wherever it needs to go using the same request structure all the way through. The I/O handlers would then transparently perform any required crypto. This should make it easier to perform RMW cycles if needed. The potentially common functions and structs, however, by their names all proclaim themselves to be associated with the read side of things. The bulk of these changes alter this in the following ways: - Rename struct netfs_read_{,sub}request to netfs_io_{,sub}request. - Rename some enums, members and flags to make them more appropriate. - Adjust some comments to match. - Drop "read"/"rreq" from the names of common functions. For instance, netfs_get_read_request() becomes netfs_get_request(). - The ->init_rreq() and ->issue_op() methods become ->init_request() and ->issue_read(). I've kept the latter as a read-specific function and in another branch added an ->issue_write() method. The driver source is then reorganised into a number of files: fs/netfs/buffered_read.c Create read reqs to the pagecache fs/netfs/io.c Dispatchers for read and write reqs fs/netfs/main.c Some general miscellaneous bits fs/netfs/objects.c Alloc, get and put functions fs/netfs/stats.c Optional procfs statistics. and future development can be fitted into this scheme, e.g.: fs/netfs/buffered_write.c Modify the pagecache fs/netfs/buffered_flush.c Writeback from the pagecache fs/netfs/direct_read.c DIO read support fs/netfs/direct_write.c DIO write support fs/netfs/unbuffered_write.c Write modifications directly back Beyond the above changes, there are also some changes that affect how things work: - Make fscache_end_operation() generally available. - In the netfs tracing header, generate enums from the symbol -> string mapping tables rather than manually coding them. - Add a struct for filesystems that uses netfslib to put into their inode wrapper structs to hold extra state that netfslib is interested in, such as the fscache cookie. This allows netfslib functions to be set in filesystem operation tables and jumped to directly without having to have a filesystem wrapper. - Add a member to the struct added above to track the remote inode length as that may differ if local modifications are buffered. We may need to supply an appropriate EOF pointer when storing data (in AFS for example). - Pass extra information to netfs_alloc_request() so that the ->init_request() hook can access it and retain information to indicate the origin of the operation. - Make the ->init_request() hook return an error, thereby allowing a filesystem that isn't allowed to cache an inode (ceph or cifs, for example) to skip readahead. - Switch to using refcount_t for subrequests and add tracepoints to log refcount changes for the request and subrequest structs. - Add a function to consolidate dispatching a read request. Similar code is used in three places and another couple are likely to be added in the future" Link: https://lore.kernel.org/all/2639515.1648483225@warthog.procyon.org.uk/ * tag 'netfs-prep-20220318' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: afs: Maintain netfs_i_context::remote_i_size netfs: Keep track of the actual remote file size netfs: Split some core bits out into their own file netfs: Split fs/netfs/read_helper.c netfs: Rename read_helper.c to io.c netfs: Prepare to split read_helper.c netfs: Add a function to consolidate beginning a read netfs: Add a netfs inode context ceph: Make ceph_init_request() check caps on readahead netfs: Change ->init_request() to return an error code netfs: Refactor arguments for netfs_alloc_read_request netfs: Adjust the netfs_failure tracepoint to indicate non-subreq lines netfs: Trace refcounting on the netfs_io_subrequest struct netfs: Trace refcounting on the netfs_io_request struct netfs: Adjust the netfs_rreq tracepoint slightly netfs: Split netfs_io_* object handling out netfs: Finish off rename of netfs_read_request to netfs_io_request netfs: Rename netfs_read_*request to netfs_io_*request netfs: Generate enums from trace symbol mapping lists fscache: export fscache_end_operation()
| * netfs: Finish off rename of netfs_read_request to netfs_io_requestDavid Howells2022-03-181-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Adjust helper function names and comments after mass rename of struct netfs_read_*request to struct netfs_io_*request. Changes ======= ver #2) - Make the changes in the docs also. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> cc: linux-cachefs@redhat.com Link: https://lore.kernel.org/r/164622992433.3564931.6684311087845150271.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/164678196111.1200972.5001114956865989528.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/164692892567.2099075.13895804222087028813.stgit@warthog.procyon.org.uk/ # v3
| * netfs: Rename netfs_read_*request to netfs_io_*requestDavid Howells2022-03-181-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rename netfs_read_*request to netfs_io_*request so that the same structures can be used for the write helpers too. perl -p -i -e 's/netfs_read_(request|subrequest)/netfs_io_$1/g' \ `git grep -l 'netfs_read_\(sub\|\)request'` perl -p -i -e 's/nr_rd_ops/nr_outstanding/g' \ `git grep -l nr_rd_ops` perl -p -i -e 's/nr_wr_ops/nr_copy_ops/g' \ `git grep -l nr_wr_ops` perl -p -i -e 's/netfs_read_source/netfs_io_source/g' \ `git grep -l 'netfs_read_source'` perl -p -i -e 's/netfs_io_request_ops/netfs_request_ops/g' \ `git grep -l 'netfs_io_request_ops'` perl -p -i -e 's/init_rreq/init_request/g' \ `git grep -l 'init_rreq'` Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> cc: linux-cachefs@redhat.com Link: https://lore.kernel.org/r/164622988070.3564931.7089670190434315183.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/164678195157.1200972.366609966927368090.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/164692891535.2099075.18435198075367420588.stgit@warthog.procyon.org.uk/ # v3
* | fs: remove kiocb.ki_hintChristoph Hellwig2022-03-081-2/+0
|/ | | | | | | | | | | This field is entirely unused now except for a tracepoint in f2fs, so remove it. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Link: https://lore.kernel.org/r/20220308060529.736277-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* netfs, cachefiles: Add a method to query presence of data in the cacheDavid Howells2022-02-011-0/+59
| | | | | | | | | | | | Add a netfs_cache_ops method by which a network filesystem can ask the cache about what data it has available and where so that it can make a multipage read more efficient. Signed-off-by: David Howells <dhowells@redhat.com> cc: linux-cachefs@redhat.com Acked-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Rohith Surabattula <rohiths@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
* cachefiles: Calculate the blockshift in terms of bytes, not pagesDavid Howells2022-01-211-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Cachefiles keeps track of how much space is available on the backing filesystem and refuses new writes permission to start if there isn't enough (we especially don't want ENOSPC happening). It also tracks the amount of data pending in DIO writes (cache->b_writing) and reduces the amount of free space available by this amount before deciding if it can set up a new write. However, the old fscache I/O API was very much page-granularity dependent and, as such, cachefiles's cache->bshift was meant to be a multiplier to get from PAGE_SIZE to block size (ie. a blocksize of 512 would give a shift of 3 for a 4KiB page) - and this was incorrectly being used to turn the number of bytes in a DIO write into a number of blocks, leading to a massive over estimation of the amount of data in flight. Fix this by changing cache->bshift to be a multiplier from bytes to blocksize and deal with quantities of blocks, not quantities of pages. Fix also the rounding in the calculation in cachefiles_write() which needs a "- 1" inserting. Fixes: 047487c947e8 ("cachefiles: Implement the I/O routines") Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> cc: linux-cachefs@redhat.com Link: https://lore.kernel.org/r/164251398954.3435901.7138806620218474123.stgit@warthog.procyon.org.uk/ # v1
* fscache, cachefiles: Display stats of no-space eventsDavid Howells2022-01-071-2/+5
| | | | | | | | | | | | | Add stat counters of no-space events that caused caching not to happen and display in /proc/fs/fscache/stats. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> cc: linux-cachefs@redhat.com Link: https://lore.kernel.org/r/163819653216.215744.17210522251617386509.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/163906958369.143852.7257100711818401748.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/163967166917.1823006.14842444049198947892.stgit@warthog.procyon.org.uk/ # v3 Link: https://lore.kernel.org/r/164021566184.640689.4417328329632709265.stgit@warthog.procyon.org.uk/ # v4
* cachefiles: Implement the I/O routinesDavid Howells2022-01-071-0/+514
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Implement the I/O routines for cachefiles. There are two sets of routines here: preparation and actual I/O. Preparation for read involves looking to see whether there is data present, and how much. Netfslib tells us what it wants us to do and we have the option of adjusting shrinking and telling it whether to read from the cache, download from the server or simply clear a region. Preparation for write involves checking for space and defending against possibly running short of space, if necessary punching out a hole in the file so that we don't leave old data in the cache if we update the coherency information. Then there's a read routine and a write routine. They wait for the cookie state to move to something appropriate and then start a potentially asynchronous direct I/O operation upon it. Changes ======= ver #2: - Fix a misassigned variable[1]. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> cc: linux-cachefs@redhat.com Link: https://lore.kernel.org/YaZOCk9zxApPattb@archlinux-ax161/ [1] Link: https://lore.kernel.org/r/163819647945.215744.17827962047487125939.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/163906954666.143852.1504887120569779407.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/163967163110.1823006.9206718511874339672.stgit@warthog.procyon.org.uk/ # v3 Link: https://lore.kernel.org/r/164021562168.640689.8802250542405732391.stgit@warthog.procyon.org.uk/ # v4
* cachefiles: Implement begin and end I/O operationDavid Howells2022-01-071-0/+57
| | | | | | | | | | | | | | | | | | | | | | | | | Implement the methods for beginning and ending an I/O operation. When called to begin an I/O operation, we are guaranteed that the cookie has reached a certain stage (we're called by fscache after it has done a suitable wait). If a file is available, we paste a ref over into the cache resources for the I/O routines to use. This means that the object can be invalidated whilst the I/O is ongoing without the need to synchronise as the file pointer in the object is replaced, but the file pointer in the cache resources is unaffected. Ending the operation just requires ditching any refs we have and dropping the access guarantee that fscache got for us on the cookie. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> cc: linux-cachefs@redhat.com Link: https://lore.kernel.org/r/163819645033.215744.2199344081658268312.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/163906951916.143852.9531384743995679857.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/163967161222.1823006.4461476204800357263.stgit@warthog.procyon.org.uk/ # v3 Link: https://lore.kernel.org/r/164021559030.640689.3684291785218094142.stgit@warthog.procyon.org.uk/ # v4
* cachefiles: Delete the cachefiles driver pending rewriteDavid Howells2022-01-071-420/+0
| | | | | | | | | | | | | Delete the code from the cachefiles driver to make it easier to rewrite and resubmit in a logical manner. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> cc: linux-cachefs@redhat.com Link: https://lore.kernel.org/r/163819577641.215744.12718114397770666596.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/163906883770.143852.4149714614981373410.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/163967076066.1823006.7175712134577687753.stgit@warthog.procyon.org.uk/ # v3 Link: https://lore.kernel.org/r/164021483619.640689.7586546280515844702.stgit@warthog.procyon.org.uk/ # v4
* fs: get rid of the res2 iocb->ki_complete argumentJens Axboe2021-10-251-6/+6
| | | | | | | | | | | The second argument was only used by the USB gadget code, yet everyone pays the overhead of passing a zero to be passed into aio, where it ends up being part of the aio res2 value. Now that everybody is passing in zero, kill off the extra argument. Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* cachefiles: Use file_inode() rather than accessing ->f_inodeDavid Howells2021-08-251-2/+2
| | | | | | | | | Use the file_inode() helper rather than accessing ->f_inode directly. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> cc: linux-cachefs@redhat.com Link: https://lore.kernel.org/r/162431192403.2908479.4590814090994846904.stgit@warthog.procyon.org.uk/
* netfs: Move cookie debug ID to struct netfs_cache_resourcesDavid Howells2021-08-251-1/+1
| | | | | | | | | | | | Move the cookie debug ID from struct netfs_read_request to struct netfs_cache_resources and drop the 'cookie_' prefix. This makes it available for things that want to use netfs_cache_resources without having a netfs_read_request. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> cc: linux-cachefs@redhat.com Link: https://lore.kernel.org/r/162431190784.2908479.13386972676539789127.stgit@warthog.procyon.org.uk/
* fscache, cachefiles: Add alternate API to use kiocb for read/write to cacheDavid Howells2021-04-231-0/+420
Add an alternate API by which the cache can be accessed through a kiocb, doing async DIO, rather than using the current API that tells the cache where all the pages are. The new API is intended to be used in conjunction with the netfs helper library. A filesystem must pick one or the other and not mix them. Filesystems wanting to use the new API must #define FSCACHE_USE_NEW_IO_API before #including the header. This prevents them from continuing to use the old API at the same time as there are incompatibilities in how the PG_fscache page bit is used. Changes: v6: - Provide a routine to shape a write so that the start and length can be aligned for DIO[3]. v4: - Use the vfs_iocb_iter_read/write() helpers[1] - Move initial definition of fscache_begin_read_operation() here. - Remove a commented-out line[2] - Combine ki->term_func calls in cachefiles_read_complete()[2]. - Remove explicit NULL initialiser[2]. - Remove extern on func decl[2]. - Put in param names on func decl[2]. - Remove redundant else[2]. - Fill out the kdoc comment for fscache_begin_read_operation(). - Rename fs/fscache/page2.c to io.c to match later patches. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-and-tested-by: Jeff Layton <jlayton@kernel.org> Tested-by: Dave Wysochanski <dwysocha@redhat.com> Tested-By: Marc Dionne <marc.dionne@auristor.com> cc: Christoph Hellwig <hch@lst.de> cc: linux-cachefs@redhat.com cc: linux-afs@lists.infradead.org cc: linux-nfs@vger.kernel.org cc: linux-cifs@vger.kernel.org cc: ceph-devel@vger.kernel.org cc: v9fs-developer@lists.sourceforge.net cc: linux-fsdevel@vger.kernel.org Link: https://lore.kernel.org/r/20210216102614.GA27555@lst.de/ [1] Link: https://lore.kernel.org/r/20210216084230.GA23669@lst.de/ [2] Link: https://lore.kernel.org/r/161781047695.463527.7463536103593997492.stgit@warthog.procyon.org.uk/ [3] Link: https://lore.kernel.org/r/161118142558.1232039.17993829899588971439.stgit@warthog.procyon.org.uk/ # rfc Link: https://lore.kernel.org/r/161161037850.2537118.8819808229350326503.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/161340402057.1303470.8038373593844486698.stgit@warthog.procyon.org.uk/ # v3 Link: https://lore.kernel.org/r/161539545919.286939.14573472672781434757.stgit@warthog.procyon.org.uk/ # v4 Link: https://lore.kernel.org/r/161653801477.2770958.10543270629064934227.stgit@warthog.procyon.org.uk/ # v5 Link: https://lore.kernel.org/r/161789084517.6155.12799689829859169640.stgit@warthog.procyon.org.uk/ # v6