kernel/git/stable/linux.git/fs/netfs, branch linux-5.18.y

netfs: do not unlock and put the folio twice

2022-07-22T08:21:42+00:00

[ Upstream commit fac47b43c760ea90e64b895dba60df0327be7775 ] check_write_begin() will unlock and put the folio when return non-zero. So we should avoid unlocking and putting it twice in netfs layer. Change the way ->check_write_begin() works in the following two ways: (1) Pass it a pointer to the folio pointer, allowing it to unlock and put the folio prior to doing the stuff it wants to do, provided it clears the folio pointer. (2) Change the return values such that 0 with folio pointer set means continue, 0 with folio pointer cleared means re-get and all error codes indicating an error (no special treatment for -EAGAIN). [ bagasdotme: use Sphinx code text syntax for *foliop pointer ] Cc: stable@vger.kernel.org Link: https://tracker.ceph.com/issues/56423 Link: https://lore.kernel.org/r/cf169f43-8ee7-8697-25da-0204d1b4343e@redhat.com Co-developed-by: David Howells Signed-off-by: Xiubo Li Signed-off-by: David Howells Signed-off-by: Bagas Sanjaya Signed-off-by: Ilya Dryomov Signed-off-by: Sasha Levin

netfs: Fix gcc-12 warning by embedding vfs inode in netfs_i_context

2022-06-22T12:28:12+00:00

commit 874c8ca1e60b2c564a48f7e7acc40d328d5c8733 upstream. While randstruct was satisfied with using an open-coded "void *" offset cast for the netfs_i_context <-> inode casting, __builtin_object_size() as used by FORTIFY_SOURCE was not as easily fooled. This was causing the following complaint[1] from gcc v12: In file included from include/linux/string.h:253, from include/linux/ceph/ceph_debug.h:7, from fs/ceph/inode.c:2: In function 'fortify_memset_chk', inlined from 'netfs_i_context_init' at include/linux/netfs.h:326:2, inlined from 'ceph_alloc_inode' at fs/ceph/inode.c:463:2: include/linux/fortify-string.h:242:25: warning: call to '__write_overflow_field' declared with attribute warning: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Wattribute-warning] 242 | __write_overflow_field(p_size_field, size); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Fix this by embedding a struct inode into struct netfs_i_context (which should perhaps be renamed to struct netfs_inode). The struct inode vfs_inode fields are then removed from the 9p, afs, ceph and cifs inode structs and vfs_inode is then simply changed to "netfs.inode" in those filesystems. Further, rename netfs_i_context to netfs_inode, get rid of the netfs_inode() function that converted a netfs_i_context pointer to an inode pointer (that can now be done with &ctx->inode) and rename the netfs_i_context() function to netfs_inode() (which is now a wrapper around container_of()). Most of the changes were done with: perl -p -i -e 's/vfs_inode/netfs.inode/'g \ `git grep -l 'vfs_inode' -- fs/{9p,afs,ceph,cifs}/*.[ch]` Kees suggested doing it with a pair structure[2] and a special declarator to insert that into the network filesystem's inode wrapper[3], but I think it's cleaner to embed it - and then it doesn't matter if struct randomisation reorders things. Dave Chinner suggested using a filesystem-specific VFS_I() function in each filesystem to convert that filesystem's own inode wrapper struct into the VFS inode struct[4]. Version #2: - Fix a couple of missed name changes due to a disabled cifs option. - Rename nfs_i_context to nfs_inode - Use "netfs" instead of "nic" as the member name in per-fs inode wrapper structs. [ This also undoes commit 507160f46c55 ("netfs: gcc-12: temporarily disable '-Wattribute-warning' for now") that is no longer needed ] Fixes: bc899ee1c898 ("netfs: Add a netfs inode context") Reported-by: Jeff Layton Signed-off-by: David Howells Reviewed-by: Jeff Layton Reviewed-by: Kees Cook Reviewed-by: Xiubo Li cc: Jonathan Corbet cc: Eric Van Hensbergen cc: Latchesar Ionkov cc: Dominique Martinet cc: Christian Schoenebeck cc: Marc Dionne cc: Ilya Dryomov cc: Steve French cc: William Kucharski cc: "Matthew Wilcox (Oracle)" cc: Dave Chinner cc: linux-doc@vger.kernel.org cc: v9fs-developer@lists.sourceforge.net cc: linux-afs@lists.infradead.org cc: ceph-devel@vger.kernel.org cc: linux-cifs@vger.kernel.org cc: samba-technical@lists.samba.org cc: linux-fsdevel@vger.kernel.org cc: linux-hardening@vger.kernel.org Link: https://lore.kernel.org/r/d2ad3a3d7bdd794c6efb562d2f2b655fb67756b9.camel@kernel.org/ [1] Link: https://lore.kernel.org/r/20220517210230.864239-1-keescook@chromium.org/ [2] Link: https://lore.kernel.org/r/20220518202212.2322058-1-keescook@chromium.org/ [3] Link: https://lore.kernel.org/r/20220524101205.GI2306852@dread.disaster.area/ [4] Link: https://lore.kernel.org/r/165296786831.3591209.12111293034669289733.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/165305805651.4094995.7763502506786714216.stgit@warthog.procyon.org.uk # v2 Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

netfs: Split some core bits out into their own file

2022-03-18T09:29:05+00:00

Split some core bits out into their own file. More bits will be added to this file later. Signed-off-by: David Howells Reviewed-by: Jeff Layton cc: linux-cachefs@redhat.com Link: https://lore.kernel.org/r/164623006934.3564931.17932680017894039748.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/164678218407.1200972.1731208226140990280.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/164692920944.2099075.11990502173226013856.stgit@warthog.procyon.org.uk/ # v3

netfs: Split fs/netfs/read_helper.c

2022-03-18T09:29:05+00:00

Split fs/netfs/read_helper.c into two pieces, one to deal with buffered writes and one to deal with the I/O mechanism. Changes ======= ver #2) - Add kdoc reference to new file. Signed-off-by: David Howells Reviewed-by: Jeff Layton cc: linux-cachefs@redhat.com Link: https://lore.kernel.org/r/164623005586.3564931.6149556072728481767.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/164678217075.1200972.5101072043126828757.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/164692919953.2099075.7156989585513833046.stgit@warthog.procyon.org.uk/ # v3

netfs: Rename read_helper.c to io.c

2022-03-18T09:29:05+00:00

Rename the read_helper.c file to io.c before splitting out the buffered read functions and some other bits. Changes ======= ver #2) - Rename read_helper.c before splitting. Signed-off-by: David Howells Reviewed-by: Jeff Layton cc: linux-cachefs@redhat.com Link: https://lore.kernel.org/r/164678216109.1200972.16567696909952495832.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/164692918076.2099075.8120961172717347610.stgit@warthog.procyon.org.uk/ # v3

netfs: Prepare to split read_helper.c

2022-03-18T09:29:05+00:00

Rename netfs_rreq_unlock() to netfs_rreq_unlock_folios() to make it sound less like it's dropping a lock on an netfs_io_request struct. Remove the 'static' marker on netfs_rreq_unlock_folios() and declaring it in internal.h preparatory to splitting the file. Changes ======= ver #2) - Slide this patch to after the one adding netfs_begin_read(). - As a consequence, don't need to unstatic so many functions. Signed-off-by: David Howells Reviewed-by: Jeff Layton cc: linux-cachefs@redhat.com Link: https://lore.kernel.org/r/164623002861.3564931.17340149482236413375.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/164678215208.1200972.9761906209395002182.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/164692912709.2099075.4349905992838317797.stgit@warthog.procyon.org.uk/ # v3

netfs: Add a function to consolidate beginning a read

2022-03-18T09:29:05+00:00

Add a function to do the steps needed to begin a read request, allowing this code to be removed from several other functions and consolidated. Changes ======= ver #2) - Move before the unstaticking patch so that some functions can be left static. - Set uninitialised return code in netfs_begin_read()[1][2]. - Fixed a refleak caused by non-removal of a get from netfs_write_begin() when the request submission code got moved to netfs_begin_read(). - Use INIT_WORK() to (re-)init the request work_struct[3]. Signed-off-by: David Howells Reviewed-by: Jeff Layton cc: linux-cachefs@redhat.com Link: https://lore.kernel.org/r/20220303163826.1120936-1-nathan@kernel.org/ [1] Link: https://lore.kernel.org/r/20220303235647.1297171-1-colin.i.king@gmail.com/ [2] Link: https://lore.kernel.org/r/9d69be49081bccff44260e4c6e0049c63d6d04a1.camel@redhat.com/ [3] Link: https://lore.kernel.org/r/164623004355.3564931.7275693529042495641.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/164678214287.1200972.16734134007649832160.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/164692911113.2099075.1060868473229451371.stgit@warthog.procyon.org.uk/ # v3

netfs: Add a netfs inode context

2022-03-18T09:29:05+00:00

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 Acked-by: Jeff Layton 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

netfs: Change ->init_request() to return an error code

2022-03-18T09:24:00+00:00

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 Reviewed-by: Jeff Layton 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

netfs: Refactor arguments for netfs_alloc_read_request

2022-03-18T09:24:00+00:00

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 Co-developed-by: David Howells Signed-off-by: David Howells 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