summaryrefslogtreecommitdiff
path: root/include/linux/netfs.h
AgeCommit message (Collapse)AuthorFilesLines
2022-03-18netfs: Keep track of the actual remote file sizeDavid Howells1-0/+16
Provide a place in which to keep track of the actual remote file size in the netfs context. This is needed because inode->i_size will be updated as we buffer writes in the pagecache, but the server file size won't get updated until we flush them back. 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/164623013727.3564931.17659955636985232717.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/164678219305.1200972.6459431995188365134.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/164692921865.2099075.5310757978508056134.stgit@warthog.procyon.org.uk/ # v3
2022-03-18netfs: Add a netfs inode contextDavid Howells1-11/+70
Add a netfs_i_context struct that should be included in the network filesystem's own inode struct wrapper, directly after the VFS's inode struct, e.g.: struct my_inode { struct { /* These must be contiguous */ struct inode vfs_inode; struct netfs_i_context netfs_ctx; }; }; The netfs_i_context struct so far contains a single field for the network filesystem to use - the cache cookie: struct netfs_i_context { ... struct fscache_cookie *cache; }; Three functions are provided to help with this: (1) void netfs_i_context_init(struct inode *inode, const struct netfs_request_ops *ops); Initialise the netfs context and set the operations. (2) struct netfs_i_context *netfs_i_context(struct inode *inode); Find the netfs context from the VFS inode. (3) struct inode *netfs_inode(struct netfs_i_context *ctx); Find the VFS inode from the netfs context. Changes ======= ver #4) - Fix netfs_is_cache_enabled() to check cookie->cache_priv to see if a cache is present[3]. - Fix netfs_skip_folio_read() to zero out all of the page, not just some of it[3]. ver #3) - Split out the bit to move ceph cap-getting on readahead into ceph_init_request()[1]. - Stick in a comment to the netfs inode structs indicating the contiguity requirements[2]. ver #2) - Adjust documentation to match. - Use "#if IS_ENABLED()" in netfs_i_cookie(), not "#ifdef". - Move the cap check from ceph_readahead() to ceph_init_request() to be called from netfslib. - Remove ceph_readahead() and use netfs_readahead() directly instead. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Jeff Layton <jlayton@kernel.org> cc: linux-cachefs@redhat.com Link: https://lore.kernel.org/r/8af0d47f17d89c06bbf602496dd845f2b0bf25b3.camel@kernel.org/ [1] Link: https://lore.kernel.org/r/beaf4f6a6c2575ed489adb14b257253c868f9a5c.camel@kernel.org/ [2] Link: https://lore.kernel.org/r/3536452.1647421585@warthog.procyon.org.uk/ [3] Link: https://lore.kernel.org/r/164622984545.3564931.15691742939278418580.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/164678213320.1200972.16807551936267647470.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/164692909854.2099075.9535537286264248057.stgit@warthog.procyon.org.uk/ # v3 Link: https://lore.kernel.org/r/306388.1647595110@warthog.procyon.org.uk/ # v4
2022-03-18netfs: Change ->init_request() to return an error codeDavid Howells1-1/+1
Change the request initialisation function to return an error code so that the network filesystem can return a failure (ENOMEM, for example). This will also allow ceph to abort a ->readahead() op if the server refuses to give it a cap allowing local caching from within the netfslib framework (errors aren't passed back through ->readahead(), so returning, say, -ENOBUFS will cause the op to be aborted). 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/164678212401.1200972.16537041523832944934.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/164692905398.2099075.5238033621684646524.stgit@warthog.procyon.org.uk/ # v3
2022-03-18netfs: Refactor arguments for netfs_alloc_read_requestDavid Howells1-0/+7
Pass start and len to the rreq allocator. This should ensure that the fields are set so that ->init_request() can use them. Also add a parameter to indicates the origin of the request. Ceph can use this to tell whether to get caps. Changes ======= ver #3) - Change the author to me as Jeff feels that most of the patch is my changes now. ver #2) - Show the request origin in the netfs_rreq tracepoint. Signed-off-by: Jeff Layton <jlayton@kernel.org> Co-developed-by: David Howells <dhowells@redhat.com> Signed-off-by: David Howells <dhowells@redhat.com> cc: linux-cachefs@redhat.com Link: https://lore.kernel.org/r/164622989020.3564931.17517006047854958747.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/164678208569.1200972.12153682697842916557.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/164692904155.2099075.14717645623034355995.stgit@warthog.procyon.org.uk/ # v3
2022-03-18netfs: Trace refcounting on the netfs_io_subrequest structDavid Howells1-1/+7
Add refcount tracing for the netfs_io_subrequest structure. Changes ======= ver #3) - Switch 'W=' to 'R=' in the traceline to match other request debug IDs. 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/164622998584.3564931.5052255990645723639.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/164678202603.1200972.14726007419792315578.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/164692901860.2099075.4845820886851239935.stgit@warthog.procyon.org.uk/ # v3
2022-03-18netfs: Trace refcounting on the netfs_io_request structDavid Howells1-1/+1
Add refcount tracing for the netfs_io_request structure. Changes ======= ver #3) - Switch 'W=' to 'R=' in the traceline to match other request debug IDs. 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/164622997668.3564931.14456171619219324968.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/164678200943.1200972.7241495532327787765.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/164692900920.2099075.11847712419940675791.stgit@warthog.procyon.org.uk/ # v3
2022-03-18netfs: Finish off rename of netfs_read_request to netfs_io_requestDavid Howells1-11/+11
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
2022-03-18netfs: Rename netfs_read_*request to netfs_io_*requestDavid Howells1-21/+21
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
2022-02-01netfs, cachefiles: Add a method to query presence of data in the cacheDavid Howells1-0/+7
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>
2022-01-07netfs: Pass more information on how to deal with a hole in the cacheDavid Howells1-1/+10
Pass more information to the cache on how to deal with a hole if it encounters one when trying to read from the cache. Three options are provided: (1) NETFS_READ_HOLE_IGNORE. Read the hole along with the data, assuming it to be a punched-out extent by the backing filesystem. (2) NETFS_READ_HOLE_CLEAR. If there's a hole, erase the requested region of the cache and clear the read buffer. (3) NETFS_READ_HOLE_FAIL. Fail the read if a hole is detected. 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/163819612321.215744.9738308885948264476.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/163906914460.143852.6284247083607910189.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/163967119923.1823006.15637375885194297582.stgit@warthog.procyon.org.uk/ # v3 Link: https://lore.kernel.org/r/164021519762.640689.16994364383313159319.stgit@warthog.procyon.org.uk/ # v4
2022-01-07fscache: Implement cookie invalidationDavid Howells1-0/+1
Add a function to invalidate the cache behind a cookie: void fscache_invalidate(struct fscache_cookie *cookie, const void *aux_data, loff_t size, unsigned int flags) This causes any cached data for the specified cookie to be discarded. If the cookie is marked as being in use, a new cache object will be created if possible and future I/O will use that instead. In-flight I/O should be abandoned (writes) or reconsidered (reads). Each time it is called cookie->inval_counter is incremented and this can be used to detect invalidation at the end of an I/O operation. The coherency data attached to the cookie can be updated and the cookie size should be reset. One flag is available, FSCACHE_INVAL_DIO_WRITE, which should be used to indicate invalidation due to a DIO write on a file. This will temporarily disable caching for this cookie. Changes ======= ver #2: - Should only change to inval state if can get access to cache. 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/163819602231.215744.11206598147269491575.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/163906909707.143852.18056070560477964891.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/163967107447.1823006.5945029409592119962.stgit@warthog.procyon.org.uk/ # v3 Link: https://lore.kernel.org/r/164021512640.640689.11418616313147754172.stgit@warthog.procyon.org.uk/ # v4
2022-01-07netfs: Pass a flag to ->prepare_write() to say if there's no alloc'd spaceDavid Howells1-1/+2
Pass a flag to ->prepare_write() to indicate if there's definitely no space allocated in the cache yet (for instance if we've already checked as we were asked to do a read). 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/163819583123.215744.12783808230464471417.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/163906886835.143852.6689886781122679769.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/163967079100.1823006.12889542712309574359.stgit@warthog.procyon.org.uk/ # v3 Link: https://lore.kernel.org/r/164021489334.640689.3131206613015409076.stgit@warthog.procyon.org.uk/ # v4
2021-11-11netfs, 9p, afs, ceph: Use foliosDavid Howells1-6/+6
Convert the netfs helper library to use folios throughout, convert the 9p and afs filesystems to use folios in their file I/O paths and convert the ceph filesystem to use just enough folios to compile. With these changes, afs passes -g quick xfstests. Changes ======= ver #5: - Got rid of folio_end{io,_read,_write}() and inlined the stuff it does instead (Willy decided he didn't want this after all). ver #4: - Fixed a bug in afs_redirty_page() whereby it didn't set the next page index in the loop and returned too early. - Simplified a check in v9fs_vfs_write_folio_locked()[1]. - Undid a change to afs_symlink_readpage()[1]. - Used offset_in_folio() in afs_write_end()[1]. - Changed from using page_endio() to folio_end{io,_read,_write}()[1]. ver #2: - Add 9p foliation. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Tested-by: Jeff Layton <jlayton@kernel.org> Tested-by: Dominique Martinet <asmadeus@codewreck.org> Tested-by: kafs-testing@auristor.com cc: Matthew Wilcox (Oracle) <willy@infradead.org> cc: Marc Dionne <marc.dionne@auristor.com> cc: Ilya Dryomov <idryomov@gmail.com> cc: Dominique Martinet <asmadeus@codewreck.org> cc: v9fs-developer@lists.sourceforge.net cc: linux-afs@lists.infradead.org cc: ceph-devel@vger.kernel.org cc: linux-cachefs@redhat.com Link: https://lore.kernel.org/r/YYKa3bfQZxK5/wDN@casper.infradead.org/ [1] Link: https://lore.kernel.org/r/2408234.1628687271@warthog.procyon.org.uk/ # rfc Link: https://lore.kernel.org/r/162877311459.3085614.10601478228012245108.stgit@warthog.procyon.org.uk/ Link: https://lore.kernel.org/r/162981153551.1901565.3124454657133703341.stgit@warthog.procyon.org.uk/ Link: https://lore.kernel.org/r/163005745264.2472992.9852048135392188995.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/163584187452.4023316.500389675405550116.stgit@warthog.procyon.org.uk/ # v3 Link: https://lore.kernel.org/r/163649328026.309189.1124218109373941936.stgit@warthog.procyon.org.uk/ # v4 Link: https://lore.kernel.org/r/163657852454.834781.9265101983152100556.stgit@warthog.procyon.org.uk/ # v5
2021-09-27fs/netfs: Add folio fscache functionsMatthew Wilcox (Oracle)1-27/+48
Match the page writeback functions by adding folio_start_fscache(), folio_end_fscache(), folio_wait_fscache() and folio_wait_fscache_killable(). Remove set_page_private_2(). Also rewrite the kernel-doc to describe when to use the function rather than what the function does, and include the kernel-doc in the appropriate rst file. Saves 31 bytes of text in netfs_rreq_unlock() due to set_page_fscache() calling page_folio() once instead of three times. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: William Kucharski <william.kucharski@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Mike Rapoport <rppt@linux.ibm.com> Reviewed-by: David Howells <dhowells@redhat.com>
2021-09-27mm/filemap: Add folio private_2 functionsMatthew Wilcox (Oracle)1-3/+3
end_page_private_2() becomes folio_end_private_2(), wait_on_page_private_2() becomes folio_wait_private_2() and wait_on_page_private_2_killable() becomes folio_wait_private_2_killable(). Adjust the fscache equivalents to call page_folio() before calling these functions to avoid adding wrappers. Ends up costing 1 byte of text in ceph & netfs, but the core shrinks by three calls to page_folio(). Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: William Kucharski <william.kucharski@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Howells <dhowells@redhat.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
2021-08-25netfs: Move cookie debug ID to struct netfs_cache_resourcesDavid Howells1-1/+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/
2021-04-23netfs: Define an interface to talk to a cacheDavid Howells1-0/+55
Add an interface to the netfs helper library for reading data from the cache instead of downloading it from the server and support for writing data just downloaded or cleared to the cache. The API passes an iov_iter to the cache read/write routines to indicate the data/buffer to be used. This is done using the ITER_XARRAY type to provide direct access to the netfs inode's pagecache. When the netfs's ->begin_cache_operation() method is called, this must fill in the cache_resources in the netfs_read_request struct, including the netfs_cache_ops used by the helper lib to talk to the cache. The helper lib does not directly access the cache. Changes: v6: - Call trace_netfs_read() after beginning the cache op so that the cookie debug ID can be logged[3]. - Don't record the error from writing to the cache. We don't want to pass it back to the netfs[4]. - Fix copy-to-cache subreq amalgamation to not round up as it goes along otherwise it overcalculates the length of the write[5]. v5: - Use end_page_fscache() rather than unlock_page_fscache()[2]. v4: - Added flag to netfs_subreq_terminated() to indicate that the caller may have been running async and stuff that might sleep needs punting to a workqueue (can't use in_softirq()[1]). - Add missing inc of netfs_n_rh_read stat. - Move initial definition of fscache_begin_read_operation() elsewhere. - Need to call op->begin_cache_operation() from netfs_write_begin(). 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: Matthew Wilcox <willy@infradead.org> cc: linux-mm@kvack.org 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/20210216084230.GA23669@lst.de/ [1] Link: https://lore.kernel.org/r/2499407.1616505440@warthog.procyon.org.uk/ [2] Link: https://lore.kernel.org/r/161781045123.463527.14533348855710902201.stgit@warthog.procyon.org.uk/ [3] Link: https://lore.kernel.org/r/161781046256.463527.18158681600085556192.stgit@warthog.procyon.org.uk/ [4] Link: https://lore.kernel.org/r/161781047695.463527.7463536103593997492.stgit@warthog.procyon.org.uk/ [5] Link: https://lore.kernel.org/r/161118141321.1232039.8296910406755622458.stgit@warthog.procyon.org.uk/ # rfc Link: https://lore.kernel.org/r/161161036700.2537118.11170748455436854978.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/161340399569.1303470.1138884774643385730.stgit@warthog.procyon.org.uk/ # v3 Link: https://lore.kernel.org/r/161539542874.286939.13337898213448136687.stgit@warthog.procyon.org.uk/ # v4 Link: https://lore.kernel.org/r/161653799826.2770958.9015430297426331950.stgit@warthog.procyon.org.uk/ # v5 Link: https://lore.kernel.org/r/161789081462.6155.3853904866933313256.stgit@warthog.procyon.org.uk/ # v6
2021-04-23netfs: Add write_begin helperDavid Howells1-0/+8
Add a helper to do the pre-reading work for the netfs write_begin address space op. Changes v6: - Fixed a missing rreq put in netfs_write_begin()[3]. - Use DEFINE_READAHEAD()[4]. v5: - Made the wait for PG_fscache in netfs_write_begin() killable[2]. v4: - Added flag to netfs_subreq_terminated() to indicate that the caller may have been running async and stuff that might sleep needs punting to a workqueue (can't use in_softirq()[1]). 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: Matthew Wilcox <willy@infradead.org> cc: linux-mm@kvack.org 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/20210216084230.GA23669@lst.de/ [1] Link: https://lore.kernel.org/r/2499407.1616505440@warthog.procyon.org.uk/ [2] Link: https://lore.kernel.org/r/161781042127.463527.9154479794406046987.stgit@warthog.procyon.org.uk/ [3] Link: https://lore.kernel.org/r/1234933.1617886271@warthog.procyon.org.uk/ [4] Link: https://lore.kernel.org/r/160588543960.3465195.2792938973035886168.stgit@warthog.procyon.org.uk/ # rfc Link: https://lore.kernel.org/r/161118140165.1232039.16418853874312234477.stgit@warthog.procyon.org.uk/ # rfc Link: https://lore.kernel.org/r/161161035539.2537118.15674887534950908530.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/161340398368.1303470.11242918276563276090.stgit@warthog.procyon.org.uk/ # v3 Link: https://lore.kernel.org/r/161539541541.286939.1889738674057013729.stgit@warthog.procyon.org.uk/ # v4 Link: https://lore.kernel.org/r/161653798616.2770958.17213315845968485563.stgit@warthog.procyon.org.uk/ # v5 Link: https://lore.kernel.org/r/161789080530.6155.1011847312392330491.stgit@warthog.procyon.org.uk/ # v6
2021-04-23netfs: Gather statsDavid Howells1-0/+1
Gather statistics from the netfs interface that can be exported through a seqfile. This is intended to be called by a later patch when viewing /proc/fs/fscache/stats. 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: Matthew Wilcox <willy@infradead.org> cc: linux-mm@kvack.org 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/161118139247.1232039.10556850937548511068.stgit@warthog.procyon.org.uk/ # rfc Link: https://lore.kernel.org/r/161161034669.2537118.2761232524997091480.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/161340397101.1303470.17581910581108378458.stgit@warthog.procyon.org.uk/ # v3 Link: https://lore.kernel.org/r/161539539959.286939.6794352576462965914.stgit@warthog.procyon.org.uk/ # v4 Link: https://lore.kernel.org/r/161653797700.2770958.5801990354413178228.stgit@warthog.procyon.org.uk/ # v5 Link: https://lore.kernel.org/r/161789079281.6155.17141344853277186500.stgit@warthog.procyon.org.uk/ # v6
2021-04-23netfs: Add tracepointsDavid Howells1-0/+1
Add three tracepoints to track the activity of the read helpers: (1) netfs/netfs_read This logs entry to the read helpers and also expansion of the range in a readahead request. (2) netfs/netfs_rreq This logs the progress of netfs_read_request objects which track read requests. A read request may be a compound of multiple subrequests. (3) netfs/netfs_sreq This logs the progress of netfs_read_subrequest objects, which track the contributions from various sources to a read request. 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: Matthew Wilcox <willy@infradead.org> cc: linux-mm@kvack.org 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/161118138060.1232039.5353374588021776217.stgit@warthog.procyon.org.uk/ # rfc Link: https://lore.kernel.org/r/161161033468.2537118.14021843889844001905.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/161340395843.1303470.7355519662919639648.stgit@warthog.procyon.org.uk/ # v3 Link: https://lore.kernel.org/r/161539538693.286939.10171713520419106334.stgit@warthog.procyon.org.uk/ # v4 Link: https://lore.kernel.org/r/161653796447.2770958.1870655382450862155.stgit@warthog.procyon.org.uk/ # v5 Link: https://lore.kernel.org/r/161789078003.6155.17814844411672989942.stgit@warthog.procyon.org.uk/ # v6
2021-04-23netfs: Provide readahead and readpage netfs helpersDavid Howells1-0/+83
Add a pair of helper functions: (*) netfs_readahead() (*) netfs_readpage() to do the work of handling a readahead or a readpage, where the page(s) that form part of the request may be split between the local cache, the server or just require clearing, and may be single pages and transparent huge pages. This is all handled within the helper. Note that while both will read from the cache if there is data present, only netfs_readahead() will expand the request beyond what it was asked to do, and only netfs_readahead() will write back to the cache. netfs_readpage(), on the other hand, is synchronous and only fetches the page (which might be a THP) it is asked for. The netfs gives the helper parameters from the VM, the cache cookie it wants to use (or NULL) and a table of operations (only one of which is mandatory): (*) expand_readahead() [optional] Called to allow the netfs to request an expansion of a readahead request to meet its own alignment requirements. This is done by changing rreq->start and rreq->len. (*) clamp_length() [optional] Called to allow the netfs to cut down a subrequest to meet its own boundary requirements. If it does this, the helper will generate additional subrequests until the full request is satisfied. (*) is_still_valid() [optional] Called to find out if the data just read from the cache has been invalidated and must be reread from the server. (*) issue_op() [required] Called to ask the netfs to issue a read to the server. The subrequest describes the read. The read request holds information about the file being accessed. The netfs can cache information in rreq->netfs_priv. Upon completion, the netfs should set the error, transferred and can also set FSCACHE_SREQ_CLEAR_TAIL and then call fscache_subreq_terminated(). (*) done() [optional] Called after the pages have been unlocked. The read request is still pinning the file and mapping and may still be pinning pages with PG_fscache. rreq->error indicates any error that has been accumulated. (*) cleanup() [optional] Called when the helper is disposing of a finished read request. This allows the netfs to clear rreq->netfs_priv. Netfs support is enabled with CONFIG_NETFS_SUPPORT=y. It will be built even if CONFIG_FSCACHE=n and in this case much of it should be optimised away, allowing the filesystem to use it even when caching is disabled. Changes: v5: - Comment why netfs_readahead() is putting pages[2]. - Use page_file_mapping() rather than page->mapping[2]. - Use page_index() rather than page->index[2]. - Use set_page_fscache()[3] rather then SetPageFsCache() as this takes an appropriate ref too[4]. v4: - Folded in a kerneldoc comment fix. - Folded in a fix for the error handling in the case that ENOMEM occurs. - Added flag to netfs_subreq_terminated() to indicate that the caller may have been running async and stuff that might sleep needs punting to a workqueue (can't use in_softirq()[1]). 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: Matthew Wilcox <willy@infradead.org> cc: linux-mm@kvack.org 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/20210216084230.GA23669@lst.de/ [1] Link: https://lore.kernel.org/r/20210321014202.GF3420@casper.infradead.org/ [2] Link: https://lore.kernel.org/r/2499407.1616505440@warthog.procyon.org.uk/ [3] Link: https://lore.kernel.org/r/CAHk-=wh+2gbF7XEjYc=HV9w_2uVzVf7vs60BPz0gFA=+pUm3ww@mail.gmail.com/ [4] Link: https://lore.kernel.org/r/160588497406.3465195.18003475695899726222.stgit@warthog.procyon.org.uk/ # rfc Link: https://lore.kernel.org/r/161118136849.1232039.8923686136144228724.stgit@warthog.procyon.org.uk/ # rfc Link: https://lore.kernel.org/r/161161032290.2537118.13400578415247339173.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/161340394873.1303470.6237319335883242536.stgit@warthog.procyon.org.uk/ # v3 Link: https://lore.kernel.org/r/161539537375.286939.16642940088716990995.stgit@warthog.procyon.org.uk/ # v4 Link: https://lore.kernel.org/r/161653795430.2770958.4947584573720000554.stgit@warthog.procyon.org.uk/ # v5 Link: https://lore.kernel.org/r/161789076581.6155.6745849361504760209.stgit@warthog.procyon.org.uk/ # v6
2021-04-23netfs, mm: Add set/end/wait_on_page_fscache() aliasesDavid Howells1-0/+57
Add set/end/wait_on_page_fscache() as aliases of set/end/wait_page_private_2(). These allow a page to marked with PG_fscache, the flag to be removed and waiters woken and waiting for the flag to be cleared. A ref on the page is also taken and dropped. [Linus suggested putting the fscache-themed functions into the caching-specific headers rather than pagemap.h[1]] Changes: v5: - Mirror the changes to the core routines[2]. Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: Jeff Layton <jlayton@kernel.org> Tested-by: Dave Wysochanski <dwysocha@redhat.com> Tested-By: Marc Dionne <marc.dionne@auristor.com> cc: Linus Torvalds <torvalds@linux-foundation.org> cc: Matthew Wilcox <willy@infradead.org> cc: linux-mm@kvack.org 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/1330473.1612974547@warthog.procyon.org.uk/ Link: https://lore.kernel.org/r/CAHk-=wjgA-74ddehziVk=XAEMTKswPu1Yw4uaro1R3ibs27ztw@mail.gmail.com/ [1] Link: https://lore.kernel.org/r/161340393568.1303470.4997526899111310530.stgit@warthog.procyon.org.uk/ # v3 Link: https://lore.kernel.org/r/161539536093.286939.5076448803512118764.stgit@warthog.procyon.org.uk/ # v4 Link: https://lore.kernel.org/r/2499407.1616505440@warthog.procyon.org.uk/ [2] Link: https://lore.kernel.org/r/161653793873.2770958.12157243390965814502.stgit@warthog.procyon.org.uk/ # v5 Link: https://lore.kernel.org/r/161789075327.6155.7432127924219092385.stgit@warthog.procyon.org.uk/ # v6
2021-04-23netfs, mm: Move PG_fscache helper funcs to linux/netfs.hDavid Howells1-0/+29
Move the PG_fscache related helper funcs (such as SetPageFsCache()) to linux/netfs.h rather than linux/fscache.h as the intention is to move to a model where they're used by the network filesystem and the helper library, but not by fscache/cachefiles itself. Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: Jeff Layton <jlayton@kernel.org> Tested-by: Dave Wysochanski <dwysocha@redhat.com> Tested-By: Marc Dionne <marc.dionne@auristor.com> cc: Matthew Wilcox <willy@infradead.org> cc: linux-mm@kvack.org 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/161340392347.1303470.18065131603507621762.stgit@warthog.procyon.org.uk/ # v3 Link: https://lore.kernel.org/r/161539534516.286939.6265142985563005000.stgit@warthog.procyon.org.uk/ # v4 Link: https://lore.kernel.org/r/161653792959.2770958.5386546945273988117.stgit@warthog.procyon.org.uk/ # v5 Link: https://lore.kernel.org/r/161789073997.6155.18442271115255650614.stgit@warthog.procyon.org.uk/ # v6
generated by cgit v1.2.3 (git 2.39.0) at 2024-08-15 15:34:47 +0300