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linux-stable/fs/netfs/internal.h

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netfs: Provide readahead and readpage netfs helpers 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
2020-05-13 16:41:20 +00:00
/* SPDX-License-Identifier: GPL-2.0-or-later */
/* Internal definitions for network filesystem support
*
* Copyright (C) 2021 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*/
netfs: Split netfs_io_* object handling out Split netfs_io_* object handling out into a file that's going to contain object allocation, get and put routines. 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/164622995118.3564931.6089530629052064470.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/164678197044.1200972.11511937252083343775.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/164692894693.2099075.7831091294248735173.stgit@warthog.procyon.org.uk/ # v3
2022-02-17 13:30:38 +00:00
#include <linux/netfs.h>
netfs: Add a netfs inode context 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
2021-06-29 21:37:05 +00:00
#include <linux/fscache.h>
netfs: Split netfs_io_* object handling out Split netfs_io_* object handling out into a file that's going to contain object allocation, get and put routines. 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/164622995118.3564931.6089530629052064470.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/164678197044.1200972.11511937252083343775.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/164692894693.2099075.7831091294248735173.stgit@warthog.procyon.org.uk/ # v3
2022-02-17 13:30:38 +00:00
#include <trace/events/netfs.h>
netfs: Provide readahead and readpage netfs helpers 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
2020-05-13 16:41:20 +00:00
#ifdef pr_fmt
#undef pr_fmt
#endif
#define pr_fmt(fmt) "netfs: " fmt
netfs: Prepare to split read_helper.c 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 <dhowells@redhat.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> 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
2022-03-01 15:55:15 +00:00
/*
* buffered_read.c
*/
void netfs_rreq_unlock_folios(struct netfs_io_request *rreq);
netfs: Rename read_helper.c to io.c 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 <dhowells@redhat.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> 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
2022-03-07 21:57:24 +00:00
/*
* io.c
*/
int netfs_begin_read(struct netfs_io_request *rreq, bool sync);
netfs: Split some core bits out into their own file Split some core bits out into their own file. More bits will be added to this file later. 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/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
2022-03-01 15:25:00 +00:00
/*
* main.c
*/
extern unsigned int netfs_debug;
netfs: Split netfs_io_* object handling out Split netfs_io_* object handling out into a file that's going to contain object allocation, get and put routines. 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/164622995118.3564931.6089530629052064470.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/164678197044.1200972.11511937252083343775.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/164692894693.2099075.7831091294248735173.stgit@warthog.procyon.org.uk/ # v3
2022-02-17 13:30:38 +00:00
/*
* objects.c
*/
netfs: Refactor arguments for netfs_alloc_read_request 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
2021-08-26 13:24:42 +00:00
struct netfs_io_request *netfs_alloc_request(struct address_space *mapping,
struct file *file,
loff_t start, size_t len,
enum netfs_io_origin origin);
netfs: Trace refcounting on the netfs_io_request struct 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
2022-02-17 21:13:05 +00:00
void netfs_get_request(struct netfs_io_request *rreq, enum netfs_rreq_ref_trace what);
netfs: Split netfs_io_* object handling out Split netfs_io_* object handling out into a file that's going to contain object allocation, get and put routines. 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/164622995118.3564931.6089530629052064470.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/164678197044.1200972.11511937252083343775.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/164692894693.2099075.7831091294248735173.stgit@warthog.procyon.org.uk/ # v3
2022-02-17 13:30:38 +00:00
void netfs_clear_subrequests(struct netfs_io_request *rreq, bool was_async);
netfs: Trace refcounting on the netfs_io_request struct 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
2022-02-17 21:13:05 +00:00
void netfs_put_request(struct netfs_io_request *rreq, bool was_async,
enum netfs_rreq_ref_trace what);
netfs: Split netfs_io_* object handling out Split netfs_io_* object handling out into a file that's going to contain object allocation, get and put routines. 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/164622995118.3564931.6089530629052064470.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/164678197044.1200972.11511937252083343775.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/164692894693.2099075.7831091294248735173.stgit@warthog.procyon.org.uk/ # v3
2022-02-17 13:30:38 +00:00
struct netfs_io_subrequest *netfs_alloc_subrequest(struct netfs_io_request *rreq);
netfs: Trace refcounting on the netfs_io_request struct 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
2022-02-17 21:13:05 +00:00
static inline void netfs_see_request(struct netfs_io_request *rreq,
enum netfs_rreq_ref_trace what)
{
trace_netfs_rreq_ref(rreq->debug_id, refcount_read(&rreq->ref), what);
}
netfs: Gather stats 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
2020-11-03 11:32:41 +00:00
/*
* stats.c
*/
#ifdef CONFIG_NETFS_STATS
extern atomic_t netfs_n_rh_readahead;
extern atomic_t netfs_n_rh_readpage;
extern atomic_t netfs_n_rh_rreq;
extern atomic_t netfs_n_rh_sreq;
extern atomic_t netfs_n_rh_download;
extern atomic_t netfs_n_rh_download_done;
extern atomic_t netfs_n_rh_download_failed;
extern atomic_t netfs_n_rh_download_instead;
extern atomic_t netfs_n_rh_read;
extern atomic_t netfs_n_rh_read_done;
extern atomic_t netfs_n_rh_read_failed;
extern atomic_t netfs_n_rh_zero;
extern atomic_t netfs_n_rh_short_read;
extern atomic_t netfs_n_rh_write;
netfs: Add write_begin helper 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
2020-09-22 10:06:07 +00:00
extern atomic_t netfs_n_rh_write_begin;
netfs: Gather stats 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
2020-11-03 11:32:41 +00:00
extern atomic_t netfs_n_rh_write_done;
extern atomic_t netfs_n_rh_write_failed;
netfs: Add write_begin helper 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
2020-09-22 10:06:07 +00:00
extern atomic_t netfs_n_rh_write_zskip;
netfs: Gather stats 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
2020-11-03 11:32:41 +00:00
static inline void netfs_stat(atomic_t *stat)
{
atomic_inc(stat);
}
static inline void netfs_stat_d(atomic_t *stat)
{
atomic_dec(stat);
}
#else
netfs: Provide readahead and readpage netfs helpers 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
2020-05-13 16:41:20 +00:00
#define netfs_stat(x) do {} while(0)
#define netfs_stat_d(x) do {} while(0)
netfs: Gather stats 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
2020-11-03 11:32:41 +00:00
#endif
netfs: Provide readahead and readpage netfs helpers 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
2020-05-13 16:41:20 +00:00
netfs: Add a netfs inode context 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
2021-06-29 21:37:05 +00:00
/*
* Miscellaneous functions.
*/
netfs: Fix gcc-12 warning by embedding vfs inode in netfs_i_context 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 <jlayton@kernel.org> Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Xiubo Li <xiubli@redhat.com> cc: Jonathan Corbet <corbet@lwn.net> cc: Eric Van Hensbergen <ericvh@gmail.com> cc: Latchesar Ionkov <lucho@ionkov.net> cc: Dominique Martinet <asmadeus@codewreck.org> cc: Christian Schoenebeck <linux_oss@crudebyte.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: Ilya Dryomov <idryomov@gmail.com> cc: Steve French <smfrench@gmail.com> cc: William Kucharski <william.kucharski@oracle.com> cc: "Matthew Wilcox (Oracle)" <willy@infradead.org> cc: Dave Chinner <david@fromorbit.com> 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 <torvalds@linux-foundation.org>
2022-06-09 20:46:04 +00:00
static inline bool netfs_is_cache_enabled(struct netfs_inode *ctx)
netfs: Add a netfs inode context 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
2021-06-29 21:37:05 +00:00
{
#if IS_ENABLED(CONFIG_FSCACHE)
struct fscache_cookie *cookie = ctx->cache;
return fscache_cookie_valid(cookie) && cookie->cache_priv &&
fscache_cookie_enabled(cookie);
#else
return false;
#endif
}
netfs: Provide readahead and readpage netfs helpers 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
2020-05-13 16:41:20 +00:00
/*****************************************************************************/
/*
* debug tracing
*/
#define dbgprintk(FMT, ...) \
printk("[%-6.6s] "FMT"\n", current->comm, ##__VA_ARGS__)
#define kenter(FMT, ...) dbgprintk("==> %s("FMT")", __func__, ##__VA_ARGS__)
#define kleave(FMT, ...) dbgprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
#define kdebug(FMT, ...) dbgprintk(FMT, ##__VA_ARGS__)
#ifdef __KDEBUG
#define _enter(FMT, ...) kenter(FMT, ##__VA_ARGS__)
#define _leave(FMT, ...) kleave(FMT, ##__VA_ARGS__)
#define _debug(FMT, ...) kdebug(FMT, ##__VA_ARGS__)
#elif defined(CONFIG_NETFS_DEBUG)
#define _enter(FMT, ...) \
do { \
if (netfs_debug) \
kenter(FMT, ##__VA_ARGS__); \
} while (0)
#define _leave(FMT, ...) \
do { \
if (netfs_debug) \
kleave(FMT, ##__VA_ARGS__); \
} while (0)
#define _debug(FMT, ...) \
do { \
if (netfs_debug) \
kdebug(FMT, ##__VA_ARGS__); \
} while (0)
#else
#define _enter(FMT, ...) no_printk("==> %s("FMT")", __func__, ##__VA_ARGS__)
#define _leave(FMT, ...) no_printk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
#define _debug(FMT, ...) no_printk(FMT, ##__VA_ARGS__)
#endif
Reference in a new issue Copy permalink