mirror_ubuntu-kernels/include
David Howells 2ff1e97587 netfs: Replace PG_fscache by setting folio->private and marking dirty
When dirty data is being written to the cache, setting/waiting on/clearing
the fscache flag is always done in tandem with setting/waiting on/clearing
the writeback flag.  The netfslib buffered write routines wait on and set
both flags and the write request cleanup clears both flags, so the fscache
flag is almost superfluous.

The reason it isn't superfluous is because the fscache flag is also used to
indicate that data just read from the server is being written to the cache.
The flag is used to prevent a race involving overlapping direct-I/O writes
to the cache.

Change this to indicate that a page is in need of being copied to the cache
by placing a magic value in folio->private and marking the folios dirty.
Then when the writeback code sees a folio marked in this way, it only
writes it to the cache and not to the server.

If a folio that has this magic value set is modified, the value is just
replaced and the folio will then be uplodaded too.

With this, PG_fscache is no longer required by the netfslib core, 9p and
afs.

Ceph and nfs, however, still need to use the old PG_fscache-based tracking.
To deal with this, a flag, NETFS_ICTX_USE_PGPRIV2, now has to be set on the
flags in the netfs_inode struct for those filesystems.  This reenables the
use of PG_fscache in that inode.  9p and afs use the netfslib write helpers
so get switched over; cifs, for the moment, does page-by-page manual access
to the cache, so doesn't use PG_fscache and is unaffected.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: Matthew Wilcox (Oracle) <willy@infradead.org>
cc: Eric Van Hensbergen <ericvh@kernel.org>
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: Xiubo Li <xiubli@redhat.com>
cc: Steve French <sfrench@samba.org>
cc: Paulo Alcantara <pc@manguebit.com>
cc: Ronnie Sahlberg <ronniesahlberg@gmail.com>
cc: Shyam Prasad N <sprasad@microsoft.com>
cc: Tom Talpey <tom@talpey.com>
cc: Bharath SM <bharathsm@microsoft.com>
cc: Trond Myklebust <trond.myklebust@hammerspace.com>
cc: Anna Schumaker <anna@kernel.org>
cc: netfs@lists.linux.dev
cc: v9fs@lists.linux.dev
cc: linux-afs@lists.infradead.org
cc: ceph-devel@vger.kernel.org
cc: linux-cifs@vger.kernel.org
cc: linux-nfs@vger.kernel.org
cc: linux-fsdevel@vger.kernel.org
cc: linux-mm@kvack.org
2024-04-29 15:01:42 +01:00
..
acpi ACPI: bus: allow _UID matching for integer zero 2024-04-08 16:57:51 +02:00
asm-generic sched: Add missing memory barrier in switch_mm_cid 2024-04-16 13:59:45 +02:00
clocksource
crypto This update includes the following changes: 2024-03-15 14:46:54 -07:00
drm drm fixes for 6.9-rc1 2024-03-21 19:04:31 -07:00
dt-bindings Char/Misc and other driver subsystem updates for 6.9-rc1 2024-03-21 13:21:31 -07:00
keys
kunit
kvm KVM: arm64: Fix host-programmed guest events in nVHE 2024-03-26 01:51:44 -07:00
linux netfs: Replace PG_fscache by setting folio->private and marking dirty 2024-04-29 15:01:42 +01:00
math-emu
media media updates for v6.9-rc1 2024-03-15 11:36:54 -07:00
memory
misc
net af_unix: Suppress false-positive lockdep splat for spin_lock() in __unix_gc(). 2024-04-25 08:37:02 -07:00
pcmcia
ras
rdma
rv
scsi scsi: sd: Fix TCG OPAL unlock on system resume 2024-03-25 15:46:12 -04:00
soc Char/Misc and other driver subsystem updates for 6.9-rc1 2024-03-21 13:21:31 -07:00
sound ASoC: Fixes for v6.9 2024-04-05 08:48:12 +02:00
target
trace netfs: Replace PG_fscache by setting folio->private and marking dirty 2024-04-29 15:01:42 +01:00
uapi drm fixes for 6.9-rc6 2024-04-26 10:47:18 -07:00
ufs
vdso vdso: Use CONFIG_PAGE_SHIFT in vdso/datapage.h 2024-04-03 21:50:04 +02:00
video
xen