linux/fs
David Howells 94d30ae90a FS-Cache: Provide the ability to enable/disable cookies
Provide the ability to enable and disable fscache cookies.  A disabled cookie
will reject or ignore further requests to:

	Acquire a child cookie
	Invalidate and update backing objects
	Check the consistency of a backing object
	Allocate storage for backing page
	Read backing pages
	Write to backing pages

but still allows:

	Checks/waits on the completion of already in-progress objects
	Uncaching of pages
	Relinquishment of cookies

Two new operations are provided:

 (1) Disable a cookie:

	void fscache_disable_cookie(struct fscache_cookie *cookie,
				    bool invalidate);

     If the cookie is not already disabled, this locks the cookie against other
     dis/enablement ops, marks the cookie as being disabled, discards or
     invalidates any backing objects and waits for cessation of activity on any
     associated object.

     This is a wrapper around a chunk split out of fscache_relinquish_cookie(),
     but it reinitialises the cookie such that it can be reenabled.

     All possible failures are handled internally.  The caller should consider
     calling fscache_uncache_all_inode_pages() afterwards to make sure all page
     markings are cleared up.

 (2) Enable a cookie:

	void fscache_enable_cookie(struct fscache_cookie *cookie,
				   bool (*can_enable)(void *data),
				   void *data)

     If the cookie is not already enabled, this locks the cookie against other
     dis/enablement ops, invokes can_enable() and, if the cookie is not an
     index cookie, will begin the procedure of acquiring backing objects.

     The optional can_enable() function is passed the data argument and returns
     a ruling as to whether or not enablement should actually be permitted to
     begin.

     All possible failures are handled internally.  The cookie will only be
     marked as enabled if provisional backing objects are allocated.

A later patch will introduce these to NFS.  Cookie enablement during nfs_open()
is then contingent on i_writecount <= 0.  can_enable() checks for a race
between open(O_RDONLY) and open(O_WRONLY/O_RDWR).  This simplifies NFS's cookie
handling and allows us to get rid of open(O_RDONLY) accidentally introducing
caching to an inode that's open for writing already.

One operation has its API modified:

 (3) Acquire a cookie.

	struct fscache_cookie *fscache_acquire_cookie(
		struct fscache_cookie *parent,
		const struct fscache_cookie_def *def,
		void *netfs_data,
		bool enable);

     This now has an additional argument that indicates whether the requested
     cookie should be enabled by default.  It doesn't need the can_enable()
     function because the caller must prevent multiple calls for the same netfs
     object and it doesn't need to take the enablement lock because no one else
     can get at the cookie before this returns.

Signed-off-by: David Howells <dhowells@redhat.com
2013-09-27 18:40:25 +01:00
..
9p FS-Cache: Provide the ability to enable/disable cookies 2013-09-27 18:40:25 +01:00
adfs truncate: drop 'oldsize' truncate_pagecache() parameter 2013-09-12 15:38:02 -07:00
affs truncate: drop 'oldsize' truncate_pagecache() parameter 2013-09-12 15:38:02 -07:00
afs FS-Cache: Provide the ability to enable/disable cookies 2013-09-27 18:40:25 +01:00
autofs4 autofs4: close the races around autofs4_notify_daemon() 2013-09-16 19:16:38 -04:00
befs [readdir] convert befs 2013-06-29 12:56:55 +04:00
bfs truncate: drop 'oldsize' truncate_pagecache() parameter 2013-09-12 15:38:02 -07:00
btrfs Merge branch 'akpm' (patches from Andrew Morton) 2013-09-12 15:44:27 -07:00
cachefiles FS-Cache: Provide the ability to enable/disable cookies 2013-09-27 18:40:25 +01:00
ceph FS-Cache: Provide the ability to enable/disable cookies 2013-09-27 18:40:25 +01:00
cifs FS-Cache: Provide the ability to enable/disable cookies 2013-09-27 18:40:25 +01:00
coda helper for reading ->d_count 2013-07-05 18:59:33 +04:00
configfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2013-07-14 11:42:26 -07:00
cramfs [readdir] convert f2fs 2013-06-29 12:56:46 +04:00
debugfs debugfs: debugfs_remove_recursive() must not rely on list_empty(d_subdirs) 2013-07-31 12:16:31 -04:00
devpts fs: Limit sys_mount to only request filesystem modules (Part 2). 2013-03-07 01:08:55 -08:00
dlm dlm: remove signal blocking 2013-08-12 15:22:43 -05:00
ecryptfs ecryptfs: avoid ctx initialization race 2013-09-06 16:58:18 -07:00
efivarfs efivarfs: we can use simple_lookup() now 2013-07-14 17:48:35 +04:00
efs efs: iget_locked() doesn't return an ERR_PTR() 2013-08-24 12:10:22 -04:00
exofs truncate: drop 'oldsize' truncate_pagecache() parameter 2013-09-12 15:38:02 -07:00
exportfs exportfs: don't assume that ->iterate() won't feed us too long entries 2013-09-07 19:54:55 -04:00
ext2 truncate: drop 'oldsize' truncate_pagecache() parameter 2013-09-12 15:38:02 -07:00
ext3 Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs 2013-09-06 09:06:02 -07:00
ext4 Merge branch 'akpm' (patches from Andrew Morton) 2013-09-12 15:44:27 -07:00
f2fs f2fs: optimize gc for better performance 2013-09-05 13:50:32 +09:00
fat truncate: drop 'oldsize' truncate_pagecache() parameter 2013-09-12 15:38:02 -07:00
freevxfs [readdir] convert freevxfs 2013-06-29 12:56:53 +04:00
fscache FS-Cache: Provide the ability to enable/disable cookies 2013-09-27 18:40:25 +01:00
fuse truncate: drop 'oldsize' truncate_pagecache() parameter 2013-09-12 15:38:02 -07:00
gfs2 gfs2: set FILE_CREATED 2013-09-16 19:17:24 -04:00
hfs truncate: drop 'oldsize' truncate_pagecache() parameter 2013-09-12 15:38:02 -07:00
hfsplus truncate: drop 'oldsize' truncate_pagecache() parameter 2013-09-12 15:38:02 -07:00
hostfs um: hostfs: Fix writeback 2013-09-07 10:38:29 +02:00
hpfs truncate: drop 'oldsize' truncate_pagecache() parameter 2013-09-12 15:38:02 -07:00
hppfs clean up scary strncpy(dst, src, strlen(src)) uses 2013-07-03 16:07:41 -07:00
hugetlbfs cope with potentially long ->d_dname() output for shmem/hugetlb 2013-08-24 12:10:17 -04:00
isofs isofs: Refuse RW mount of the filesystem instead of making it RO 2013-07-31 22:14:50 +02:00
jbd jbd: use a single printk for jbd_debug() 2013-08-09 10:49:00 +02:00
jbd2 jbd2: Fix endian mixing problems in the checksumming code 2013-08-28 14:59:58 -04:00
jffs2 [readdir] convert jffs2 2013-06-29 12:56:47 +04:00
jfs truncate: drop 'oldsize' truncate_pagecache() parameter 2013-09-12 15:38:02 -07:00
lockd LOCKD: Don't call utsname()->nodename from nlmclnt_setlockargs 2013-08-05 15:03:46 -04:00
logfs Lots of bug fixes, cleanups and optimizations. In the bug fixes 2013-07-02 09:39:34 -07:00
minix truncate: drop 'oldsize' truncate_pagecache() parameter 2013-09-12 15:38:02 -07:00
ncpfs ncpfs: fix error return code in ncp_parse_options() 2013-07-09 10:33:25 -07:00
nfs FS-Cache: Provide the ability to enable/disable cookies 2013-09-27 18:40:25 +01:00
nfs_common nfs_common: Update the translation between nfsv3 acls linux posix acls 2013-02-13 06:15:14 -08:00
nfsd Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2013-09-12 15:01:38 -07:00
nilfs2 truncate: drop 'oldsize' truncate_pagecache() parameter 2013-09-12 15:38:02 -07:00
nls
notify fsnotify: update comments concerning locking scheme 2013-07-09 10:33:20 -07:00
ntfs truncate: drop 'oldsize' truncate_pagecache() parameter 2013-09-12 15:38:02 -07:00
ocfs2 Merge git://git.kvack.org/~bcrl/aio-next 2013-09-13 10:55:58 -07:00
omfs truncate: drop 'oldsize' truncate_pagecache() parameter 2013-09-12 15:38:02 -07:00
openpromfs [readdir] convert openpromfs 2013-06-29 12:56:32 +04:00
proc thp: account anon transparent huge pages into NR_ANON_PAGES 2013-09-12 15:38:03 -07:00
pstore pstore: Remove the messages related to compression failure 2013-09-16 09:28:29 -07:00
qnx4 [readdir] convert qnx4 2013-06-29 12:56:38 +04:00
qnx6 [readdir] convert qnx6 2013-06-29 12:56:39 +04:00
quota fs: convert fs shrinkers to new scan/count API 2013-09-10 18:56:31 -04:00
ramfs initmpfs: move rootfs code from fs/ramfs/ to init/ 2013-09-11 15:59:37 -07:00
reiserfs Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs 2013-09-06 09:06:02 -07:00
romfs [readdir] convert romfs 2013-06-29 12:56:29 +04:00
squashfs Squashfs: add corruption check for type in squashfs_readdir() 2013-09-06 04:57:54 +01:00
sysfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2013-09-07 14:36:57 -07:00
sysv truncate: drop 'oldsize' truncate_pagecache() parameter 2013-09-12 15:38:02 -07:00
ubifs Just one patch which fixes the power-cut recovery testing mode. 2013-09-16 15:36:55 -04:00
udf Merge git://git.kvack.org/~bcrl/aio-next 2013-09-13 10:55:58 -07:00
ufs truncate: drop 'oldsize' truncate_pagecache() parameter 2013-09-12 15:38:02 -07:00
xfs xfs: update #2 for v3.12-rc1 2013-09-12 16:13:41 -07:00
Kconfig efivarfs: Move to fs/efivarfs 2013-04-17 13:25:09 +01:00
Kconfig.binfmt fs: make binfmt support for #! scripts modular and removable 2013-04-30 17:04:04 -07:00
Makefile Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2013-05-01 17:51:54 -07:00
aio.c aio: rcu_read_lock protection for new rcu_dereference calls 2013-09-09 12:29:35 -04:00
anon_inodes.c fs/anon_inode: Introduce a new lib function anon_inode_getfile_private() 2013-07-16 09:32:17 -04:00
attr.c
bad_inode.c [readdir] ->readdir() is gone 2013-06-29 12:57:04 +04:00
binfmt_aout.c mm: remove free_area_cache 2013-07-10 18:11:34 -07:00
binfmt_elf.c mm: remove free_area_cache 2013-07-10 18:11:34 -07:00
binfmt_elf_fdpic.c Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2013-05-02 10:16:16 -07:00
binfmt_em86.c
binfmt_flat.c new helper: read_code() 2013-04-29 15:40:23 -04:00
binfmt_misc.c binfmt_misc: reuse string_unescape_inplace() 2013-04-30 17:04:03 -07:00
binfmt_script.c
binfmt_som.c
bio-integrity.c fs/bio-integrity: fix a potential mem leak 2013-09-11 15:58:21 -07:00
bio.c Merge branch 'for-3.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup 2013-09-03 18:25:03 -07:00
block_dev.c a trivial writeback fix 2013-09-13 23:06:40 -04:00
buffer.c mm: vmscan: take page buffers dirty and locked state into account 2013-07-03 16:07:29 -07:00
char_dev.c
compat.c [readdir] constify ->actor 2013-06-29 12:57:05 +04:00
compat_binfmt_elf.c
compat_ioctl.c compat.c: LOOP_CLR_FD is taken care of in loop.c itself... 2013-06-29 12:46:44 +04:00
coredump.c coredump: add new %P variable in core_pattern 2013-09-11 15:59:01 -07:00
coredump.h
dcache.c vfs: fix typo in comment in recent dentry work 2013-09-15 07:11:01 -04:00
dcookies.c consolidate compat lookup_dcookie() 2013-03-03 23:00:23 -05:00
direct-io.c direct-io: Use return from cmpxchg to decide of assignment happened 2013-09-09 10:47:42 -07:00
drop_caches.c shrinker: add node awareness 2013-09-10 18:56:31 -04:00
eventfd.c
eventpoll.c epoll: add a reschedule point in ep_free() 2013-09-11 15:58:50 -07:00
exec.c exec: cleanup the error handling in search_binary_handler() 2013-09-11 15:59:09 -07:00
fcntl.c vfs: add missing check for __O_TMPFILE in fcntl_init() 2013-08-05 18:25:32 +04:00
fhandle.c
file.c don't bother with deferred freeing of fdtables 2013-05-01 17:31:42 -04:00
file_table.c fs/file_table.c:fput(): make comment more truthful 2013-09-11 15:59:01 -07:00
filesystems.c fs: Limit sys_mount to only request filesystem modules. 2013-03-03 19:36:31 -08:00
fs-writeback.c a trivial writeback fix 2013-09-13 23:06:40 -04:00
fs_struct.c constify path_get/path_put and fs_struct.c stuff 2013-03-01 23:51:07 -05:00
generic_acl.c
inode.c fs: convert inode and dentry shrinking to be node aware 2013-09-10 18:56:31 -04:00
internal.h fs: convert inode and dentry shrinking to be node aware 2013-09-10 18:56:31 -04:00
ioctl.c new helper: file_inode(file) 2013-02-22 23:31:31 -05:00
ioprio.c
libfs.c make simple_lookup() usable for filesystems that set ->s_d_op 2013-07-14 17:43:25 +04:00
locks.c locks: move file_lock_list to a set of percpu hlist_heads and convert file_lock_lock to an lglock 2013-07-08 13:36:42 +04:00
mbcache.c fs: convert fs shrinkers to new scan/count API 2013-09-10 18:56:31 -04:00
mount.h get rid of full-hash scan on detaching vfsmounts 2013-04-09 14:12:52 -04:00
mpage.c
namei.c atomic_open: take care of EEXIST in no-open case with O_CREAT|O_EXCL in fs/namei.c 2013-09-17 17:08:50 -04:00
namespace.c initmpfs: move rootfs code from fs/ramfs/ to init/ 2013-09-11 15:59:37 -07:00
no-block.c
open.c vfs: improve i_op->atomic_open() documentation 2013-09-16 19:17:24 -04:00
pipe.c aio: don't include aio.h in sched.h 2013-05-07 20:16:25 -07:00
pnode.c vfs: Fix invalid ida_remove() call 2013-05-31 15:16:33 -04:00
pnode.h vfs: Don't copy mount bind mounts of /proc/<pid>/ns/mnt between namespaces 2013-08-26 18:42:15 -07:00
posix_acl.c
proc_namespace.c
read_write.c aio: Kill aio_rw_vect_retry() 2013-07-30 11:53:12 -04:00
readdir.c [readdir] constify ->actor 2013-06-29 12:57:05 +04:00
select.c net: rename include/net/ll_poll.h to include/net/busy_poll.h 2013-07-10 17:08:27 -07:00
seq_file.c seq_file: add seq_list_*_percpu helpers 2013-07-08 13:36:41 +04:00
signalfd.c switch signalfd{,4}() to COMPAT_SYSCALL_DEFINE 2013-03-03 22:58:46 -05:00
splice.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2013-07-03 09:10:19 -07:00
stack.c
stat.c quota: provide interface for readding allocated space into reserved space 2013-08-17 09:32:32 -04:00
statfs.c
super.c super: fix for destroy lrus 2013-09-10 18:56:32 -04:00
sync.c teach SYSCALL_DEFINE<n> how to deal with long long/unsigned long long 2013-03-03 22:46:22 -05:00
timerfd.c timerfd: Add alarm timers 2013-05-29 12:57:34 -07:00
utimes.c
xattr.c
xattr_acl.c