[PATCH v5 03/40] netfs, fscache: Move fs/fscache/* into fs/netfs/

David Howells
2023-12-21T13:24:23Z

There's a problem with dependencies between netfslib and fscache as each
wants to access some functions of the other. Deal with this by moving
fs/fscache/* into fs/netfs/ and renaming those files to begin with
"fscache-".

For the moment, the moved files are changed as little as possible and an
fscache module is still built. A subsequent patch will integrate them.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: Christian Brauner <christian@brauner.io>
cc: linux-fsdevel@vger.kernel.org
cc: linux-cachefs@redhat.com
---

Notes:
Changes
=======
ver #5)
- Adjust MAINTAINERS file.

MAINTAINERS | 21 ++++++----
fs/Kconfig | 1 -
fs/Makefile | 1 -
fs/fscache/Kconfig | 40 -------------------
fs/fscache/Makefile | 16 --------
fs/netfs/Kconfig | 39 ++++++++++++++++++
fs/netfs/Makefile | 14 ++++++-
fs/{fscache/cache.c => netfs/fscache_cache.c} | 0
.../cookie.c => netfs/fscache_cookie.c} | 0
.../internal.h => netfs/fscache_internal.h} | 0
fs/{fscache/io.c => netfs/fscache_io.c} | 0
fs/{fscache/main.c => netfs/fscache_main.c} | 0
fs/{fscache/proc.c => netfs/fscache_proc.c} | 0
fs/{fscache/stats.c => netfs/fscache_stats.c} | 0
.../volume.c => netfs/fscache_volume.c} | 0
fs/netfs/internal.h | 5 +++
fs/netfs/main.c | 5 ++-
17 files changed, 73 insertions(+), 69 deletions(-)
delete mode 100644 fs/fscache/Kconfig
delete mode 100644 fs/fscache/Makefile
rename fs/{fscache/cache.c => netfs/fscache_cache.c} (100%)
rename fs/{fscache/cookie.c => netfs/fscache_cookie.c} (100%)
rename fs/{fscache/internal.h => netfs/fscache_internal.h} (100%)
rename fs/{fscache/io.c => netfs/fscache_io.c} (100%)
rename fs/{fscache/main.c => netfs/fscache_main.c} (100%)
rename fs/{fscache/proc.c => netfs/fscache_proc.c} (100%)
rename fs/{fscache/stats.c => netfs/fscache_stats.c} (100%)
rename fs/{fscache/volume.c => netfs/fscache_volume.c} (100%)

diff --git a/MAINTAINERS b/MAINTAINERS
index 9104430e148e..b38e1723b505 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8135,6 +8135,19 @@ S: Supported
F: fs/iomap/
F: include/linux/iomap.h

+FILESYSTEMS [NETFS LIBRARY]
+M: David Howells <dhowells@redhat.com>
+L: linux-cachefs@redhat.com (moderated for non-subscribers)
+L: linux-fsdevel@vger.kernel.org
+S: Supported
+F: Documentation/filesystems/caching/
+F: Documentation/filesystems/netfs_library.rst
+F: fs/netfs/
+F: include/linux/fscache*.h
+F: include/linux/netfs.h
+F: include/trace/events/fscache.h
+F: include/trace/events/netfs.h
+
FINTEK F75375S HARDWARE MONITOR AND FAN CONTROLLER DRIVER
M: Riku Voipio <riku.voipio@iki.fi>
L: linux-hwmon@vger.kernel.org
@@ -8569,14 +8582,6 @@ F: Documentation/power/freezing-of-tasks.rst
F: include/linux/freezer.h
F: kernel/freezer.c

-FS-CACHE: LOCAL CACHING FOR NETWORK FILESYSTEMS
-M: David Howells <dhowells@redhat.com>
-L: linux-cachefs@redhat.com (moderated for non-subscribers)
-S: Supported
-F: Documentation/filesystems/caching/
-F: fs/fscache/
-F: include/linux/fscache*.h
-
FSCRYPT: FILE SYSTEM LEVEL ENCRYPTION SUPPORT
M: Eric Biggers <ebiggers@kernel.org>
M: Theodore Y. Ts'o <tytso@mit.edu>
diff --git a/fs/Kconfig b/fs/Kconfig
index 42837617a55b..c935c341eb6e 100644
--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -140,7 +140,6 @@ source "fs/overlayfs/Kconfig"
menu "Caches"

source "fs/netfs/Kconfig"
-source "fs/fscache/Kconfig"
source "fs/cachefiles/Kconfig"

endmenu
diff --git a/fs/Makefile b/fs/Makefile
index 75522f88e763..af7632368e98 100644
--- a/fs/Makefile
+++ b/fs/Makefile
@@ -60,7 +60,6 @@ obj-$(CONFIG_DLM) += dlm/

# Do not add any filesystems before this line
obj-$(CONFIG_NETFS_SUPPORT) += netfs/
-obj-$(CONFIG_FSCACHE) += fscache/
obj-$(CONFIG_REISERFS_FS) += reiserfs/
obj-$(CONFIG_EXT4_FS) += ext4/
# We place ext4 before ext2 so that clean ext3 root fs's do NOT mount using the
diff --git a/fs/fscache/Kconfig b/fs/fscache/Kconfig
deleted file mode 100644
index b313a978ae0a..000000000000
--- a/fs/fscache/Kconfig
+++ /dev/null
@@ -1,40 +0,0 @@
-# SPDX-License-Identifier: GPL-2.0-only
-
-config FSCACHE
- tristate "General filesystem local caching manager"
- select NETFS_SUPPORT
- help
- This option enables a generic filesystem caching manager that can be
- used by various network and other filesystems to cache data locally.
- Different sorts of caches can be plugged in, depending on the
- resources available.
-
- See Documentation/filesystems/caching/fscache.rst for more information.
-
-config FSCACHE_STATS
- bool "Gather statistical information on local caching"
- depends on FSCACHE && PROC_FS
- select NETFS_STATS
- help
- This option causes statistical information to be gathered on local
- caching and exported through file:
-
- /proc/fs/fscache/stats
-
- The gathering of statistics adds a certain amount of overhead to
- execution as there are a quite a few stats gathered, and on a
- multi-CPU system these may be on cachelines that keep bouncing
- between CPUs. On the other hand, the stats are very useful for
- debugging purposes. Saying 'Y' here is recommended.
-
- See Documentation/filesystems/caching/fscache.rst for more information.
-
-config FSCACHE_DEBUG
- bool "Debug FS-Cache"
- depends on FSCACHE
- help
- This permits debugging to be dynamically enabled in the local caching
- management module. If this is set, the debugging output may be
- enabled by setting bits in /sys/modules/fscache/parameter/debug.
-
- See Documentation/filesystems/caching/fscache.rst for more information.
diff --git a/fs/fscache/Makefile b/fs/fscache/Makefile
deleted file mode 100644
index afb090ea16c4..000000000000
--- a/fs/fscache/Makefile
+++ /dev/null
@@ -1,16 +0,0 @@
-# SPDX-License-Identifier: GPL-2.0
-#
-# Makefile for general filesystem caching code
-#
-
-fscache-y := \
- cache.o \
- cookie.o \
- io.o \
- main.o \
- volume.o
-
-fscache-$(CONFIG_PROC_FS) += proc.o
-fscache-$(CONFIG_FSCACHE_STATS) += stats.o
-
-obj-$(CONFIG_FSCACHE) := fscache.o
diff --git a/fs/netfs/Kconfig b/fs/netfs/Kconfig
index b4db21022cb4..b4378688357c 100644
--- a/fs/netfs/Kconfig
+++ b/fs/netfs/Kconfig
@@ -21,3 +21,42 @@ config NETFS_STATS
multi-CPU system these may be on cachelines that keep bouncing
between CPUs. On the other hand, the stats are very useful for
debugging purposes. Saying 'Y' here is recommended.
+
+config FSCACHE
+ tristate "General filesystem local caching manager"
+ select NETFS_SUPPORT
+ help
+ This option enables a generic filesystem caching manager that can be
+ used by various network and other filesystems to cache data locally.
+ Different sorts of caches can be plugged in, depending on the
+ resources available.
+
+ See Documentation/filesystems/caching/fscache.rst for more information.
+
+config FSCACHE_STATS
+ bool "Gather statistical information on local caching"
+ depends on FSCACHE && PROC_FS
+ select NETFS_STATS
+ help
+ This option causes statistical information to be gathered on local
+ caching and exported through file:
+
+ /proc/fs/fscache/stats
+
+ The gathering of statistics adds a certain amount of overhead to
+ execution as there are a quite a few stats gathered, and on a
+ multi-CPU system these may be on cachelines that keep bouncing
+ between CPUs. On the other hand, the stats are very useful for
+ debugging purposes. Saying 'Y' here is recommended.
+
+ See Documentation/filesystems/caching/fscache.rst for more information.
+
+config FSCACHE_DEBUG
+ bool "Debug FS-Cache"
+ depends on FSCACHE
+ help
+ This permits debugging to be dynamically enabled in the local caching
+ management module. If this is set, the debugging output may be
+ enabled by setting bits in /sys/modules/fscache/parameter/debug.
+
+ See Documentation/filesystems/caching/fscache.rst for more information.
diff --git a/fs/netfs/Makefile b/fs/netfs/Makefile
index 386d6fb92793..bbb2b824bd5e 100644
--- a/fs/netfs/Makefile
+++ b/fs/netfs/Makefile
@@ -1,5 +1,17 @@
# SPDX-License-Identifier: GPL-2.0

+fscache-y := \
+ fscache_cache.o \
+ fscache_cookie.o \
+ fscache_io.o \
+ fscache_main.o \
+ fscache_volume.o
+
+fscache-$(CONFIG_PROC_FS) += fscache_proc.o
+fscache-$(CONFIG_FSCACHE_STATS) += fscache_stats.o
+
+obj-$(CONFIG_FSCACHE) := fscache.o
+
netfs-y := \
buffered_read.o \
io.o \
@@ -9,4 +21,4 @@ netfs-y := \

netfs-$(CONFIG_NETFS_STATS) += stats.o

-obj-$(CONFIG_NETFS_SUPPORT) := netfs.o
+obj-$(CONFIG_NETFS_SUPPORT) += netfs.o
diff --git a/fs/fscache/cache.c b/fs/netfs/fscache_cache.c
similarity index 100%
rename from fs/fscache/cache.c
rename to fs/netfs/fscache_cache.c
diff --git a/fs/fscache/cookie.c b/fs/netfs/fscache_cookie.c
similarity index 100%
rename from fs/fscache/cookie.c
rename to fs/netfs/fscache_cookie.c
diff --git a/fs/fscache/internal.h b/fs/netfs/fscache_internal.h
similarity index 100%
rename from fs/fscache/internal.h
rename to fs/netfs/fscache_internal.h
diff --git a/fs/fscache/io.c b/fs/netfs/fscache_io.c
similarity index 100%
rename from fs/fscache/io.c
rename to fs/netfs/fscache_io.c
diff --git a/fs/fscache/main.c b/fs/netfs/fscache_main.c
similarity index 100%
rename from fs/fscache/main.c
rename to fs/netfs/fscache_main.c
diff --git a/fs/fscache/proc.c b/fs/netfs/fscache_proc.c
similarity index 100%
rename from fs/fscache/proc.c
rename to fs/netfs/fscache_proc.c
diff --git a/fs/fscache/stats.c b/fs/netfs/fscache_stats.c
similarity index 100%
rename from fs/fscache/stats.c
rename to fs/netfs/fscache_stats.c
diff --git a/fs/fscache/volume.c b/fs/netfs/fscache_volume.c
similarity index 100%
rename from fs/fscache/volume.c
rename to fs/netfs/fscache_volume.c
diff --git a/fs/netfs/internal.h b/fs/netfs/internal.h
index 43fac1b14e40..e96432499eb2 100644
--- a/fs/netfs/internal.h
+++ b/fs/netfs/internal.h
@@ -5,9 +5,12 @@
* Written by David Howells (dhowells@redhat.com)
*/

+#include <linux/slab.h>
+#include <linux/seq_file.h>
#include <linux/netfs.h>
#include <linux/fscache.h>
#include <trace/events/netfs.h>
+#include "fscache_internal.h"

#ifdef pr_fmt
#undef pr_fmt
@@ -107,6 +110,7 @@ static inline bool netfs_is_cache_enabled(struct netfs_inode *ctx)
/*
* debug tracing
*/
+#if 0
#define dbgprintk(FMT, ...) \
printk("[%-6.6s] "FMT"\n", current->comm, ##__VA_ARGS__)

@@ -143,3 +147,4 @@ do { \
#define _leave(FMT, ...) no_printk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
#define _debug(FMT, ...) no_printk(FMT, ##__VA_ARGS__)
#endif
+#endif
diff --git a/fs/netfs/main.c b/fs/netfs/main.c
index 068568702957..237c54a01d97 100644
--- a/fs/netfs/main.c
+++ b/fs/netfs/main.c
@@ -8,8 +8,8 @@
#include <linux/module.h>
#include <linux/export.h>
#include "internal.h"
-#define CREATE_TRACE_POINTS
-#include <trace/events/netfs.h>
+//#define CREATE_TRACE_POINTS
+//#include <trace/events/netfs.h>

MODULE_DESCRIPTION("Network fs support");
MODULE_AUTHOR("Red Hat, Inc.");
@@ -18,3 +18,4 @@ MODULE_LICENSE("GPL");
unsigned netfs_debug;
module_param_named(debug, netfs_debug, uint, S_IWUSR | S_IRUGO);
MODULE_PARM_DESC(netfs_debug, "Netfs support debugging mask");
+