[PATCH 62/64] nfs: Convert to new fscache volume/cookie API

From: David Howells
Date: Mon Nov 29 2021 - 09:40:46 EST

From: Dave Wysochanski <dwysocha@xxxxxxxxxx>

Change the nfs filesystem to support fscache's indexing rewrite and
reenable caching in nfs.

The following changes have been made:

(1) The fscache_netfs struct is no more, and there's no need to register
the filesystem as a whole.

(2) The session cookie is now an fscache_volume cookie, allocated with
fscache_acquire_volume(). That takes three parameters: a string
representing the "volume" in the index, a string naming the cache to
use (or NULL) and a u64 that conveys coherency metadata for the
volume.

For nfs, I've made it render the volume name string as:

"nfs,<ver>,<family>,<address>,<port>,<fsidH>,<fsidL>*<,param>[,<uniq>]"

(3) The fscache_cookie_def is no more and needed information is passed
directly to fscache_acquire_cookie(). The cache no longer calls back
into the filesystem, but rather metadata changes are indicated at
other times.

fscache_acquire_cookie() is passed the same keying and coherency
information as before.

(4) fscache_enable/disable_cookie() have been removed.

Call fscache_use_cookie() and fscache_unuse_cookie() when a file is
opened or closed to prevent a cache file from being culled and to keep
resources to hand that are needed to do I/O.

Unuse the cookie when a file is opened for writing. This is gated by
the NFS_INO_FSCACHE flag on the nfs_inode.

A better way might be to invalidate it with FSCACHE_INVAL_DIO_WRITE
which will keep it unused until all open files are closed.

(5) fscache_invalidate() now needs to be given uptodate auxiliary data and
a file size. It also takes a flag to indicate if this was due to a
DIO write.

(6) Call nfs_fscache_invalidate() with FSCACHE_INVAL_DIO_WRITE on a file
to which a DIO write is made.

(7) Call fscache_note_page_release() from nfs_release_page().

(8) Use a killable wait in nfs_vm_page_mkwrite() when waiting for
PG_fscache to be cleared.

(9) The functions to read and write data to/from the cache are stubbed out
pending a conversion to use netfslib.

Signed-off-by: Dave Wysochanski <dwysocha@xxxxxxxxxx>
Co-developed-by: David Howells <dhowells@xxxxxxxxxx>
Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
cc: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
cc: Anna Schumaker <anna.schumaker@xxxxxxxxxx>
cc: linux-nfs@xxxxxxxxxxxxxxx
cc: linux-cachefs@xxxxxxxxxx
---

fs/nfs/Kconfig | 2
fs/nfs/Makefile | 2
fs/nfs/client.c | 4
fs/nfs/direct.c | 2
fs/nfs/file.c | 12 +
fs/nfs/fscache-index.c | 140 ---------------
fs/nfs/fscache.c | 415 +++++++++------------------------------------
fs/nfs/fscache.h | 123 +++----------
fs/nfs/inode.c | 11 -
fs/nfs/super.c | 7 -
fs/nfs/write.c | 1
include/linux/nfs_fs_sb.h | 9 -
12 files changed, 138 insertions(+), 590 deletions(-)
delete mode 100644 fs/nfs/fscache-index.c

diff --git a/fs/nfs/Kconfig b/fs/nfs/Kconfig
index bdc11b89eac5..14a72224b657 100644
--- a/fs/nfs/Kconfig
+++ b/fs/nfs/Kconfig
@@ -170,7 +170,7 @@ config ROOT_NFS

config NFS_FSCACHE
bool "Provide NFS client caching support"
- depends on NFS_FS=m && FSCACHE_OLD_API || NFS_FS=y && FSCACHE_OLD_API=y
+ depends on NFS_FS=m && FSCACHE || NFS_FS=y && FSCACHE=y
help
Say Y here if you want NFS data to be cached locally on disc through
the general filesystem cache manager
diff --git a/fs/nfs/Makefile b/fs/nfs/Makefile
index 22d11fdc6deb..5f6db37f461e 100644
--- a/fs/nfs/Makefile
+++ b/fs/nfs/Makefile
@@ -12,7 +12,7 @@ nfs-y := client.o dir.o file.o getroot.o inode.o super.o \
export.o sysfs.o fs_context.o
nfs-$(CONFIG_ROOT_NFS) += nfsroot.o
nfs-$(CONFIG_SYSCTL) += sysctl.o
-nfs-$(CONFIG_NFS_FSCACHE) += fscache.o fscache-index.o
+nfs-$(CONFIG_NFS_FSCACHE) += fscache.o

obj-$(CONFIG_NFS_V2) += nfsv2.o
nfsv2-y := nfs2super.o proc.o nfs2xdr.o
diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index 1e4dc1ab9312..8d8b85b5a641 100644
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -183,8 +183,6 @@ struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *cl_init)
clp->cl_net = get_net(cl_init->net);

clp->cl_principal = "*";
- nfs_fscache_get_client_cookie(clp);
-
return clp;

error_cleanup:
@@ -238,8 +236,6 @@ static void pnfs_init_server(struct nfs_server *server)
*/
void nfs_free_client(struct nfs_client *clp)
{
- nfs_fscache_release_client_cookie(clp);
-
/* -EIO all pending I/O */
if (!IS_ERR(clp->cl_rpcclient))
rpc_shutdown_client(clp->cl_rpcclient);
diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c
index 9cff8709c80a..eabfdab543c8 100644
--- a/fs/nfs/direct.c
+++ b/fs/nfs/direct.c
@@ -59,6 +59,7 @@
#include "internal.h"
#include "iostat.h"
#include "pnfs.h"
+#include "fscache.h"

#define NFSDBG_FACILITY NFSDBG_VFS

@@ -959,6 +960,7 @@ ssize_t nfs_file_direct_write(struct kiocb *iocb, struct iov_iter *iter)
} else {
result = requested;
}
+ nfs_fscache_invalidate(inode, FSCACHE_INVAL_DIO_WRITE);
out_release:
nfs_direct_req_release(dreq);
out:
diff --git a/fs/nfs/file.c b/fs/nfs/file.c
index 24e7dccce355..0055e56c49fc 100644
--- a/fs/nfs/file.c
+++ b/fs/nfs/file.c
@@ -415,8 +415,7 @@ static void nfs_invalidate_page(struct page *page, unsigned int offset,
return;
/* Cancel any unstarted writes on this page */
nfs_wb_page_cancel(page_file_mapping(page)->host, page);
-
- nfs_fscache_invalidate_page(page, page->mapping->host);
+ wait_on_page_fscache(page);
}

/*
@@ -475,12 +474,11 @@ static void nfs_check_dirty_writeback(struct page *page,
static int nfs_launder_page(struct page *page)
{
struct inode *inode = page_file_mapping(page)->host;
- struct nfs_inode *nfsi = NFS_I(inode);

dfprintk(PAGECACHE, "NFS: launder_page(%ld, %llu)\n",
inode->i_ino, (long long)page_offset(page));

- nfs_fscache_wait_on_page_write(nfsi, page);
+ wait_on_page_fscache(page);
return nfs_wb_page(inode, page);
}

@@ -555,7 +553,11 @@ static vm_fault_t nfs_vm_page_mkwrite(struct vm_fault *vmf)
sb_start_pagefault(inode->i_sb);

/* make sure the cache has finished storing the page */
- nfs_fscache_wait_on_page_write(NFS_I(inode), page);
+ if (PageFsCache(page) &&
+ wait_on_page_fscache_killable(vmf->page) < 0) {
+ ret = VM_FAULT_RETRY;
+ goto out;
+ }

wait_on_bit_action(&NFS_I(inode)->flags, NFS_INO_INVALIDATING,
nfs_wait_bit_killable, TASK_KILLABLE);
diff --git a/fs/nfs/fscache-index.c b/fs/nfs/fscache-index.c
deleted file mode 100644
index 573b1da9342c..000000000000
--- a/fs/nfs/fscache-index.c
+++ /dev/null
@@ -1,140 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/* NFS FS-Cache index structure definition
- *
- * Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@xxxxxxxxxx)
- */
-
-#include <linux/init.h>
-#include <linux/kernel.h>
-#include <linux/sched.h>
-#include <linux/mm.h>
-#include <linux/nfs_fs.h>
-#include <linux/nfs_fs_sb.h>
-#include <linux/in6.h>
-#include <linux/iversion.h>
-
-#include "internal.h"
-#include "fscache.h"
-
-#define NFSDBG_FACILITY NFSDBG_FSCACHE
-
-/*
- * Define the NFS filesystem for FS-Cache. Upon registration FS-Cache sticks
- * the cookie for the top-level index object for NFS into here. The top-level
- * index can than have other cache objects inserted into it.
- */
-struct fscache_netfs nfs_fscache_netfs = {
- .name = "nfs",
- .version = 0,
-};
-
-/*
- * Register NFS for caching
- */
-int nfs_fscache_register(void)
-{
- return fscache_register_netfs(&nfs_fscache_netfs);
-}
-
-/*
- * Unregister NFS for caching
- */
-void nfs_fscache_unregister(void)
-{
- fscache_unregister_netfs(&nfs_fscache_netfs);
-}
-
-/*
- * Define the server object for FS-Cache. This is used to describe a server
- * object to fscache_acquire_cookie(). It is keyed by the NFS protocol and
- * server address parameters.
- */
-const struct fscache_cookie_def nfs_fscache_server_index_def = {
- .name = "NFS.server",
- .type = FSCACHE_COOKIE_TYPE_INDEX,
-};
-
-/*
- * Define the superblock object for FS-Cache. This is used to describe a
- * superblock object to fscache_acquire_cookie(). It is keyed by all the NFS
- * parameters that might cause a separate superblock.
- */
-const struct fscache_cookie_def nfs_fscache_super_index_def = {
- .name = "NFS.super",
- .type = FSCACHE_COOKIE_TYPE_INDEX,
-};
-
-/*
- * Consult the netfs about the state of an object
- * - This function can be absent if the index carries no state data
- * - The netfs data from the cookie being used as the target is
- * presented, as is the auxiliary data
- */
-static
-enum fscache_checkaux nfs_fscache_inode_check_aux(void *cookie_netfs_data,
- const void *data,
- uint16_t datalen,
- loff_t object_size)
-{
- struct nfs_fscache_inode_auxdata auxdata;
- struct nfs_inode *nfsi = cookie_netfs_data;
-
- if (datalen != sizeof(auxdata))
- return FSCACHE_CHECKAUX_OBSOLETE;
-
- memset(&auxdata, 0, sizeof(auxdata));
- auxdata.mtime_sec = nfsi->vfs_inode.i_mtime.tv_sec;
- auxdata.mtime_nsec = nfsi->vfs_inode.i_mtime.tv_nsec;
- auxdata.ctime_sec = nfsi->vfs_inode.i_ctime.tv_sec;
- auxdata.ctime_nsec = nfsi->vfs_inode.i_ctime.tv_nsec;
-
- if (NFS_SERVER(&nfsi->vfs_inode)->nfs_client->rpc_ops->version == 4)
- auxdata.change_attr = inode_peek_iversion_raw(&nfsi->vfs_inode);
-
- if (memcmp(data, &auxdata, datalen) != 0)
- return FSCACHE_CHECKAUX_OBSOLETE;
-
- return FSCACHE_CHECKAUX_OKAY;
-}
-
-/*
- * Get an extra reference on a read context.
- * - This function can be absent if the completion function doesn't require a
- * context.
- * - The read context is passed back to NFS in the event that a data read on the
- * cache fails with EIO - in which case the server must be contacted to
- * retrieve the data, which requires the read context for security.
- */
-static void nfs_fh_get_context(void *cookie_netfs_data, void *context)
-{
- get_nfs_open_context(context);
-}
-
-/*
- * Release an extra reference on a read context.
- * - This function can be absent if the completion function doesn't require a
- * context.
- */
-static void nfs_fh_put_context(void *cookie_netfs_data, void *context)
-{
- if (context)
- put_nfs_open_context(context);
-}
-
-/*
- * Define the inode object for FS-Cache. This is used to describe an inode
- * object to fscache_acquire_cookie(). It is keyed by the NFS file handle for
- * an inode.
- *
- * Coherency is managed by comparing the copies of i_size, i_mtime and i_ctime
- * held in the cache auxiliary data for the data storage object with those in
- * the inode struct in memory.
- */
-const struct fscache_cookie_def nfs_fscache_inode_object_def = {
- .name = "NFS.fh",
- .type = FSCACHE_COOKIE_TYPE_DATAFILE,
- .check_aux = nfs_fscache_inode_check_aux,
- .get_context = nfs_fh_get_context,
- .put_context = nfs_fh_put_context,
-};
diff --git a/fs/nfs/fscache.c b/fs/nfs/fscache.c
index d743629e05e1..b72b925beac2 100644
--- a/fs/nfs/fscache.c
+++ b/fs/nfs/fscache.c
@@ -22,24 +22,18 @@

#define NFSDBG_FACILITY NFSDBG_FSCACHE

-static struct rb_root nfs_fscache_keys = RB_ROOT;
-static DEFINE_SPINLOCK(nfs_fscache_keys_lock);
+#define NFS_MAX_KEY_LEN 1000

-/*
- * Layout of the key for an NFS server cache object.
- */
-struct nfs_server_key {
- struct {
- uint16_t nfsversion; /* NFS protocol version */
- uint32_t minorversion; /* NFSv4 minor version */
- uint16_t family; /* address family */
- __be16 port; /* IP port */
- } hdr;
- union {
- struct in_addr ipv4_addr; /* IPv4 address */
- struct in6_addr ipv6_addr; /* IPv6 address */
- };
-} __packed;
+static bool nfs_append_int(char *key, int *_len, unsigned long long x)
+{
+ if (*_len > NFS_MAX_KEY_LEN)
+ return false;
+ if (x == 0)
+ key[(*_len)++] = ',';
+ else
+ *_len += sprintf(key + *_len, ",%llx", x);
+ return true;
+}

/*
* Get the per-client index cookie for an NFS client if the appropriate mount
@@ -47,63 +41,43 @@ struct nfs_server_key {
* - We always try and get an index cookie for the client, but get filehandle
* cookies on a per-superblock basis, depending on the mount flags
*/
-void nfs_fscache_get_client_cookie(struct nfs_client *clp)
+static bool nfs_fscache_get_client_key(struct nfs_client *clp,
+ char *key, int *_len)
{
const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) &clp->cl_addr;
const struct sockaddr_in *sin = (struct sockaddr_in *) &clp->cl_addr;
- struct nfs_server_key key;
- uint16_t len = sizeof(key.hdr);

- memset(&key, 0, sizeof(key));
- key.hdr.nfsversion = clp->rpc_ops->version;
- key.hdr.minorversion = clp->cl_minorversion;
- key.hdr.family = clp->cl_addr.ss_family;
+ *_len += snprintf(key + *_len, NFS_MAX_KEY_LEN - *_len,
+ ",%u.%u,%x",
+ clp->rpc_ops->version,
+ clp->cl_minorversion,
+ clp->cl_addr.ss_family);

switch (clp->cl_addr.ss_family) {
case AF_INET:
- key.hdr.port = sin->sin_port;
- key.ipv4_addr = sin->sin_addr;
- len += sizeof(key.ipv4_addr);
- break;
+ if (!nfs_append_int(key, _len, sin->sin_port) ||
+ !nfs_append_int(key, _len, sin->sin_addr.s_addr))
+ return false;
+ return true;

case AF_INET6:
- key.hdr.port = sin6->sin6_port;
- key.ipv6_addr = sin6->sin6_addr;
- len += sizeof(key.ipv6_addr);
- break;
+ if (!nfs_append_int(key, _len, sin6->sin6_port) ||
+ !nfs_append_int(key, _len, sin6->sin6_addr.s6_addr32[0]) ||
+ !nfs_append_int(key, _len, sin6->sin6_addr.s6_addr32[1]) ||
+ !nfs_append_int(key, _len, sin6->sin6_addr.s6_addr32[2]) ||
+ !nfs_append_int(key, _len, sin6->sin6_addr.s6_addr32[3]))
+ return false;
+ return true;

default:
printk(KERN_WARNING "NFS: Unknown network family '%d'\n",
clp->cl_addr.ss_family);
- clp->fscache = NULL;
- return;
+ return false;
}
-
- /* create a cache index for looking up filehandles */
- clp->fscache = fscache_acquire_cookie(nfs_fscache_netfs.primary_index,
- &nfs_fscache_server_index_def,
- &key, len,
- NULL, 0,
- clp, 0, true);
- dfprintk(FSCACHE, "NFS: get client cookie (0x%p/0x%p)\n",
- clp, clp->fscache);
-}
-
-/*
- * Dispose of a per-client cookie
- */
-void nfs_fscache_release_client_cookie(struct nfs_client *clp)
-{
- dfprintk(FSCACHE, "NFS: releasing client cookie (0x%p/0x%p)\n",
- clp, clp->fscache);
-
- fscache_relinquish_cookie(clp->fscache, NULL, false);
- clp->fscache = NULL;
}

/*
- * Get the cache cookie for an NFS superblock. We have to handle
- * uniquification here because the cache doesn't do it for us.
+ * Get the cache cookie for an NFS superblock.
*
* The default uniquifier is just an empty string, but it may be overridden
* either by the 'fsc=xxx' option to mount, or by inheriting it from the parent
@@ -111,96 +85,53 @@ void nfs_fscache_release_client_cookie(struct nfs_client *clp)
*/
void nfs_fscache_get_super_cookie(struct super_block *sb, const char *uniq, int ulen)
{
- struct nfs_fscache_key *key, *xkey;
struct nfs_server *nfss = NFS_SB(sb);
- struct rb_node **p, *parent;
- int diff;
+ unsigned int len = 3;
+ char *key;

- nfss->fscache_key = NULL;
- nfss->fscache = NULL;
- if (!uniq) {
- uniq = "";
- ulen = 1;
+ if (uniq) {
+ nfss->fscache_uniq = kmemdup_nul(uniq, ulen, GFP_KERNEL);
+ if (!nfss->fscache_uniq)
+ return;
}

- key = kzalloc(sizeof(*key) + ulen, GFP_KERNEL);
+ key = kmalloc(NFS_MAX_KEY_LEN + 24, GFP_KERNEL);
if (!key)
return;

- key->nfs_client = nfss->nfs_client;
- key->key.super.s_flags = sb->s_flags & NFS_SB_MASK;
- key->key.nfs_server.flags = nfss->flags;
- key->key.nfs_server.rsize = nfss->rsize;
- key->key.nfs_server.wsize = nfss->wsize;
- key->key.nfs_server.acregmin = nfss->acregmin;
- key->key.nfs_server.acregmax = nfss->acregmax;
- key->key.nfs_server.acdirmin = nfss->acdirmin;
- key->key.nfs_server.acdirmax = nfss->acdirmax;
- key->key.nfs_server.fsid = nfss->fsid;
- key->key.rpc_auth.au_flavor = nfss->client->cl_auth->au_flavor;
-
- key->key.uniq_len = ulen;
- memcpy(key->key.uniquifier, uniq, ulen);
-
- spin_lock(&nfs_fscache_keys_lock);
- p = &nfs_fscache_keys.rb_node;
- parent = NULL;
- while (*p) {
- parent = *p;
- xkey = rb_entry(parent, struct nfs_fscache_key, node);
-
- if (key->nfs_client < xkey->nfs_client)
- goto go_left;
- if (key->nfs_client > xkey->nfs_client)
- goto go_right;
-
- diff = memcmp(&key->key, &xkey->key, sizeof(key->key));
- if (diff < 0)
- goto go_left;
- if (diff > 0)
- goto go_right;
-
- if (key->key.uniq_len == 0)
- goto non_unique;
- diff = memcmp(key->key.uniquifier,
- xkey->key.uniquifier,
- key->key.uniq_len);
- if (diff < 0)
- goto go_left;
- if (diff > 0)
- goto go_right;
- goto non_unique;
-
- go_left:
- p = &(*p)->rb_left;
- continue;
- go_right:
- p = &(*p)->rb_right;
+ memcpy(key, "nfs", 3);
+ if (!nfs_fscache_get_client_key(nfss->nfs_client, key, &len) ||
+ !nfs_append_int(key, &len, nfss->fsid.major) ||
+ !nfs_append_int(key, &len, nfss->fsid.minor) ||
+ !nfs_append_int(key, &len, sb->s_flags & NFS_SB_MASK) ||
+ !nfs_append_int(key, &len, nfss->flags) ||
+ !nfs_append_int(key, &len, nfss->rsize) ||
+ !nfs_append_int(key, &len, nfss->wsize) ||
+ !nfs_append_int(key, &len, nfss->acregmin) ||
+ !nfs_append_int(key, &len, nfss->acregmax) ||
+ !nfs_append_int(key, &len, nfss->acdirmin) ||
+ !nfs_append_int(key, &len, nfss->acdirmax) ||
+ !nfs_append_int(key, &len, nfss->client->cl_auth->au_flavor))
+ goto out;
+
+ if (ulen > 0) {
+ if (ulen > NFS_MAX_KEY_LEN - len)
+ goto out;
+ key[len++] = ',';
+ memcpy(key + len, uniq, ulen);
+ len += ulen;
}
-
- rb_link_node(&key->node, parent, p);
- rb_insert_color(&key->node, &nfs_fscache_keys);
- spin_unlock(&nfs_fscache_keys_lock);
- nfss->fscache_key = key;
+ key[len] = 0;

/* create a cache index for looking up filehandles */
- nfss->fscache = fscache_acquire_cookie(nfss->nfs_client->fscache,
- &nfs_fscache_super_index_def,
- &key->key,
- sizeof(key->key) + ulen,
- NULL, 0,
- nfss, 0, true);
+ nfss->fscache = fscache_acquire_volume(key,
+ NULL, /* preferred_cache */
+ 0 /* coherency_data */);
dfprintk(FSCACHE, "NFS: get superblock cookie (0x%p/0x%p)\n",
nfss, nfss->fscache);
- return;

-non_unique:
- spin_unlock(&nfs_fscache_keys_lock);
+out:
kfree(key);
- nfss->fscache_key = NULL;
- nfss->fscache = NULL;
- printk(KERN_WARNING "NFS:"
- " Cache request denied due to non-unique superblock keys\n");
}

/*
@@ -213,29 +144,9 @@ void nfs_fscache_release_super_cookie(struct super_block *sb)
dfprintk(FSCACHE, "NFS: releasing superblock cookie (0x%p/0x%p)\n",
nfss, nfss->fscache);

- fscache_relinquish_cookie(nfss->fscache, NULL, false);
+ fscache_relinquish_volume(nfss->fscache, 0, false);
nfss->fscache = NULL;
-
- if (nfss->fscache_key) {
- spin_lock(&nfs_fscache_keys_lock);
- rb_erase(&nfss->fscache_key->node, &nfs_fscache_keys);
- spin_unlock(&nfs_fscache_keys_lock);
- kfree(nfss->fscache_key);
- nfss->fscache_key = NULL;
- }
-}
-
-static void nfs_fscache_update_auxdata(struct nfs_fscache_inode_auxdata *auxdata,
- struct nfs_inode *nfsi)
-{
- memset(auxdata, 0, sizeof(*auxdata));
- auxdata->mtime_sec = nfsi->vfs_inode.i_mtime.tv_sec;
- auxdata->mtime_nsec = nfsi->vfs_inode.i_mtime.tv_nsec;
- auxdata->ctime_sec = nfsi->vfs_inode.i_ctime.tv_sec;
- auxdata->ctime_nsec = nfsi->vfs_inode.i_ctime.tv_nsec;
-
- if (NFS_SERVER(&nfsi->vfs_inode)->nfs_client->rpc_ops->version == 4)
- auxdata->change_attr = inode_peek_iversion_raw(&nfsi->vfs_inode);
+ kfree(nfss->fscache_uniq);
}

/*
@@ -254,10 +165,12 @@ void nfs_fscache_init_inode(struct inode *inode)
nfs_fscache_update_auxdata(&auxdata, nfsi);

nfsi->fscache = fscache_acquire_cookie(NFS_SB(inode->i_sb)->fscache,
- &nfs_fscache_inode_object_def,
- nfsi->fh.data, nfsi->fh.size,
- &auxdata, sizeof(auxdata),
- nfsi, nfsi->vfs_inode.i_size, false);
+ 0,
+ nfsi->fh.data, /* index_key */
+ nfsi->fh.size,
+ &auxdata, /* aux_data */
+ sizeof(auxdata),
+ i_size_read(&nfsi->vfs_inode));
}

/*
@@ -271,18 +184,14 @@ void nfs_fscache_clear_inode(struct inode *inode)

dfprintk(FSCACHE, "NFS: clear cookie (0x%p/0x%p)\n", nfsi, cookie);

- nfs_fscache_update_auxdata(&auxdata, nfsi);
- fscache_relinquish_cookie(cookie, &auxdata, false);
+ if (test_and_clear_bit(NFS_INO_FSCACHE, &NFS_I(inode)->flags)) {
+ nfs_fscache_update_auxdata(&auxdata, nfsi);
+ fscache_unuse_cookie(cookie, &auxdata, NULL);
+ }
+ fscache_relinquish_cookie(cookie, false);
nfsi->fscache = NULL;
}

-static bool nfs_fscache_can_enable(void *data)
-{
- struct inode *inode = data;
-
- return !inode_is_open_for_write(inode);
-}
-
/*
* Enable or disable caching for a file that is being opened as appropriate.
* The cookie is allocated when the inode is initialised, but is not enabled at
@@ -307,103 +216,28 @@ void nfs_fscache_open_file(struct inode *inode, struct file *filp)
struct nfs_fscache_inode_auxdata auxdata;
struct nfs_inode *nfsi = NFS_I(inode);
struct fscache_cookie *cookie = nfs_i_fscache(inode);
+ bool open_for_write = inode_is_open_for_write(inode);

if (!fscache_cookie_valid(cookie))
return;

- nfs_fscache_update_auxdata(&auxdata, nfsi);
+ fscache_use_cookie(cookie, open_for_write);

- if (inode_is_open_for_write(inode)) {
+ if (open_for_write) {
dfprintk(FSCACHE, "NFS: nfsi 0x%p disabling cache\n", nfsi);
- clear_bit(NFS_INO_FSCACHE, &nfsi->flags);
- fscache_disable_cookie(cookie, &auxdata, true);
- fscache_uncache_all_inode_pages(cookie, inode);
- } else {
- dfprintk(FSCACHE, "NFS: nfsi 0x%p enabling cache\n", nfsi);
- fscache_enable_cookie(cookie, &auxdata, nfsi->vfs_inode.i_size,
- nfs_fscache_can_enable, inode);
- if (fscache_cookie_enabled(cookie))
- set_bit(NFS_INO_FSCACHE, &NFS_I(inode)->flags);
+ nfs_fscache_update_auxdata(&auxdata, nfsi);
+ fscache_invalidate(cookie, &auxdata, i_size_read(inode),
+ FSCACHE_INVAL_DIO_WRITE);
}
}
EXPORT_SYMBOL_GPL(nfs_fscache_open_file);

-/*
- * Release the caching state associated with a page, if the page isn't busy
- * interacting with the cache.
- * - Returns true (can release page) or false (page busy).
- */
-int nfs_fscache_release_page(struct page *page, gfp_t gfp)
-{
- if (PageFsCache(page)) {
- struct fscache_cookie *cookie = nfs_i_fscache(page->mapping->host);
-
- BUG_ON(!cookie);
- dfprintk(FSCACHE, "NFS: fscache releasepage (0x%p/0x%p/0x%p)\n",
- cookie, page, NFS_I(page->mapping->host));
-
- if (!fscache_maybe_release_page(cookie, page, gfp))
- return 0;
-
- nfs_inc_fscache_stats(page->mapping->host,
- NFSIOS_FSCACHE_PAGES_UNCACHED);
- }
-
- return 1;
-}
-
-/*
- * Release the caching state associated with a page if undergoing complete page
- * invalidation.
- */
-void __nfs_fscache_invalidate_page(struct page *page, struct inode *inode)
-{
- struct fscache_cookie *cookie = nfs_i_fscache(inode);
-
- BUG_ON(!cookie);
-
- dfprintk(FSCACHE, "NFS: fscache invalidatepage (0x%p/0x%p/0x%p)\n",
- cookie, page, NFS_I(inode));
-
- fscache_wait_on_page_write(cookie, page);
-
- BUG_ON(!PageLocked(page));
- fscache_uncache_page(cookie, page);
- nfs_inc_fscache_stats(page->mapping->host,
- NFSIOS_FSCACHE_PAGES_UNCACHED);
-}
-
-/*
- * Handle completion of a page being read from the cache.
- * - Called in process (keventd) context.
- */
-static void nfs_readpage_from_fscache_complete(struct page *page,
- void *context,
- int error)
-{
- dfprintk(FSCACHE,
- "NFS: readpage_from_fscache_complete (0x%p/0x%p/%d)\n",
- page, context, error);
-
- /*
- * If the read completes with an error, mark the page with PG_checked,
- * unlock the page, and let the VM reissue the readpage.
- */
- if (!error)
- SetPageUptodate(page);
- else
- SetPageChecked(page);
- unlock_page(page);
-}
-
/*
* Retrieve a page from fscache
*/
int __nfs_readpage_from_fscache(struct nfs_open_context *ctx,
struct inode *inode, struct page *page)
{
- int ret;
-
dfprintk(FSCACHE,
"NFS: readpage_from_fscache(fsc:%p/p:%p(i:%lx f:%lx)/0x%p)\n",
nfs_i_fscache(inode), page, page->index, page->flags, inode);
@@ -413,31 +247,7 @@ int __nfs_readpage_from_fscache(struct nfs_open_context *ctx,
return 1;
}

- ret = fscache_read_or_alloc_page(nfs_i_fscache(inode),
- page,
- nfs_readpage_from_fscache_complete,
- ctx,
- GFP_KERNEL);
-
- switch (ret) {
- case 0: /* read BIO submitted (page in fscache) */
- dfprintk(FSCACHE,
- "NFS: readpage_from_fscache: BIO submitted\n");
- nfs_inc_fscache_stats(inode, NFSIOS_FSCACHE_PAGES_READ_OK);
- return ret;
-
- case -ENOBUFS: /* inode not in cache */
- case -ENODATA: /* page not in cache */
- nfs_inc_fscache_stats(inode, NFSIOS_FSCACHE_PAGES_READ_FAIL);
- dfprintk(FSCACHE,
- "NFS: readpage_from_fscache %d\n", ret);
- return 1;
-
- default:
- dfprintk(FSCACHE, "NFS: readpage_from_fscache %d\n", ret);
- nfs_inc_fscache_stats(inode, NFSIOS_FSCACHE_PAGES_READ_FAIL);
- }
- return ret;
+ return -ENOBUFS; // TODO: Use netfslib
}

/*
@@ -449,45 +259,10 @@ int __nfs_readpages_from_fscache(struct nfs_open_context *ctx,
struct list_head *pages,
unsigned *nr_pages)
{
- unsigned npages = *nr_pages;
- int ret;
-
dfprintk(FSCACHE, "NFS: nfs_getpages_from_fscache (0x%p/%u/0x%p)\n",
- nfs_i_fscache(inode), npages, inode);
-
- ret = fscache_read_or_alloc_pages(nfs_i_fscache(inode),
- mapping, pages, nr_pages,
- nfs_readpage_from_fscache_complete,
- ctx,
- mapping_gfp_mask(mapping));
- if (*nr_pages < npages)
- nfs_add_fscache_stats(inode, NFSIOS_FSCACHE_PAGES_READ_OK,
- npages);
- if (*nr_pages > 0)
- nfs_add_fscache_stats(inode, NFSIOS_FSCACHE_PAGES_READ_FAIL,
- *nr_pages);
-
- switch (ret) {
- case 0: /* read submitted to the cache for all pages */
- BUG_ON(!list_empty(pages));
- BUG_ON(*nr_pages != 0);
- dfprintk(FSCACHE,
- "NFS: nfs_getpages_from_fscache: submitted\n");
-
- return ret;
-
- case -ENOBUFS: /* some pages aren't cached and can't be */
- case -ENODATA: /* some pages aren't cached */
- dfprintk(FSCACHE,
- "NFS: nfs_getpages_from_fscache: no page: %d\n", ret);
- return 1;
-
- default:
- dfprintk(FSCACHE,
- "NFS: nfs_getpages_from_fscache: ret %d\n", ret);
- }
+ nfs_i_fscache(inode), *nr_pages, inode);

- return ret;
+ return -ENOBUFS; // TODO: Use netfslib
}

/*
@@ -496,25 +271,9 @@ int __nfs_readpages_from_fscache(struct nfs_open_context *ctx,
*/
void __nfs_readpage_to_fscache(struct inode *inode, struct page *page, int sync)
{
- int ret;
-
dfprintk(FSCACHE,
"NFS: readpage_to_fscache(fsc:%p/p:%p(i:%lx f:%lx)/%d)\n",
nfs_i_fscache(inode), page, page->index, page->flags, sync);

- ret = fscache_write_page(nfs_i_fscache(inode), page,
- inode->i_size, GFP_KERNEL);
- dfprintk(FSCACHE,
- "NFS: readpage_to_fscache: p:%p(i:%lu f:%lx) ret %d\n",
- page, page->index, page->flags, ret);
-
- if (ret != 0) {
- fscache_uncache_page(nfs_i_fscache(inode), page);
- nfs_inc_fscache_stats(inode,
- NFSIOS_FSCACHE_PAGES_WRITTEN_FAIL);
- nfs_inc_fscache_stats(inode, NFSIOS_FSCACHE_PAGES_UNCACHED);
- } else {
- nfs_inc_fscache_stats(inode,
- NFSIOS_FSCACHE_PAGES_WRITTEN_OK);
- }
+ return; // TODO: Use netfslib
}
diff --git a/fs/nfs/fscache.h b/fs/nfs/fscache.h
index 6754c8607230..0be8db67d89f 100644
--- a/fs/nfs/fscache.h
+++ b/fs/nfs/fscache.h
@@ -12,46 +12,10 @@
#include <linux/nfs_mount.h>
#include <linux/nfs4_mount.h>
#include <linux/fscache.h>
+#include <linux/iversion.h>

#ifdef CONFIG_NFS_FSCACHE

-/*
- * set of NFS FS-Cache objects that form a superblock key
- */
-struct nfs_fscache_key {
- struct rb_node node;
- struct nfs_client *nfs_client; /* the server */
-
- /* the elements of the unique key - as used by nfs_compare_super() and
- * nfs_compare_mount_options() to distinguish superblocks */
- struct {
- struct {
- unsigned long s_flags; /* various flags
- * (& NFS_MS_MASK) */
- } super;
-
- struct {
- struct nfs_fsid fsid;
- int flags;
- unsigned int rsize; /* read size */
- unsigned int wsize; /* write size */
- unsigned int acregmin; /* attr cache timeouts */
- unsigned int acregmax;
- unsigned int acdirmin;
- unsigned int acdirmax;
- } nfs_server;
-
- struct {
- rpc_authflavor_t au_flavor;
- } rpc_auth;
-
- /* uniquifier - can be used if nfs_server.flags includes
- * NFS_MOUNT_UNSHARED */
- u8 uniq_len;
- char uniquifier[0];
- } key;
-};
-
/*
* Definition of the auxiliary data attached to NFS inode storage objects
* within the cache.
@@ -69,23 +33,9 @@ struct nfs_fscache_inode_auxdata {
u64 change_attr;
};

-/*
- * fscache-index.c
- */
-extern struct fscache_netfs nfs_fscache_netfs;
-extern const struct fscache_cookie_def nfs_fscache_server_index_def;
-extern const struct fscache_cookie_def nfs_fscache_super_index_def;
-extern const struct fscache_cookie_def nfs_fscache_inode_object_def;
-
-extern int nfs_fscache_register(void);
-extern void nfs_fscache_unregister(void);
-
/*
* fscache.c
*/
-extern void nfs_fscache_get_client_cookie(struct nfs_client *);
-extern void nfs_fscache_release_client_cookie(struct nfs_client *);
-
extern void nfs_fscache_get_super_cookie(struct super_block *, const char *, int);
extern void nfs_fscache_release_super_cookie(struct super_block *);

@@ -94,7 +44,6 @@ extern void nfs_fscache_clear_inode(struct inode *);
extern void nfs_fscache_open_file(struct inode *, struct file *);

extern void __nfs_fscache_invalidate_page(struct page *, struct inode *);
-extern int nfs_fscache_release_page(struct page *, gfp_t);

extern int __nfs_readpage_from_fscache(struct nfs_open_context *,
struct inode *, struct page *);
@@ -103,25 +52,17 @@ extern int __nfs_readpages_from_fscache(struct nfs_open_context *,
struct list_head *, unsigned *);
extern void __nfs_readpage_to_fscache(struct inode *, struct page *, int);

-/*
- * wait for a page to complete writing to the cache
- */
-static inline void nfs_fscache_wait_on_page_write(struct nfs_inode *nfsi,
- struct page *page)
-{
- if (PageFsCache(page))
- fscache_wait_on_page_write(nfsi->fscache, page);
-}
-
-/*
- * release the caching state associated with a page if undergoing complete page
- * invalidation
- */
-static inline void nfs_fscache_invalidate_page(struct page *page,
- struct inode *inode)
+static inline int nfs_fscache_release_page(struct page *page, gfp_t gfp)
{
- if (PageFsCache(page))
- __nfs_fscache_invalidate_page(page, inode);
+ if (PageFsCache(page)) {
+ if (!(gfp & __GFP_DIRECT_RECLAIM) || !(gfp & __GFP_FS))
+ return false;
+ wait_on_page_fscache(page);
+ fscache_note_page_release(nfs_i_fscache(page->mapping->host));
+ nfs_inc_fscache_stats(page->mapping->host,
+ NFSIOS_FSCACHE_PAGES_UNCACHED);
+ }
+ return true;
}

/*
@@ -163,20 +104,32 @@ static inline void nfs_readpage_to_fscache(struct inode *inode,
__nfs_readpage_to_fscache(inode, page, sync);
}

-/*
- * Invalidate the contents of fscache for this inode. This will not sleep.
- */
-static inline void nfs_fscache_invalidate(struct inode *inode)
+static inline void nfs_fscache_update_auxdata(struct nfs_fscache_inode_auxdata *auxdata,
+ struct nfs_inode *nfsi)
{
- fscache_invalidate(NFS_I(inode)->fscache);
+ memset(auxdata, 0, sizeof(*auxdata));
+ auxdata->mtime_sec = nfsi->vfs_inode.i_mtime.tv_sec;
+ auxdata->mtime_nsec = nfsi->vfs_inode.i_mtime.tv_nsec;
+ auxdata->ctime_sec = nfsi->vfs_inode.i_ctime.tv_sec;
+ auxdata->ctime_nsec = nfsi->vfs_inode.i_ctime.tv_nsec;
+
+ if (NFS_SERVER(&nfsi->vfs_inode)->nfs_client->rpc_ops->version == 4)
+ auxdata->change_attr = inode_peek_iversion_raw(&nfsi->vfs_inode);
}

/*
- * Wait for an object to finish being invalidated.
+ * Invalidate the contents of fscache for this inode. This will not sleep.
*/
-static inline void nfs_fscache_wait_on_invalidate(struct inode *inode)
+static inline void nfs_fscache_invalidate(struct inode *inode, int flags)
{
- fscache_wait_on_invalidate(NFS_I(inode)->fscache);
+ struct nfs_fscache_inode_auxdata auxdata;
+ struct nfs_inode *nfsi = NFS_I(inode);
+
+ if (nfsi->fscache) {
+ nfs_fscache_update_auxdata(&auxdata, nfsi);
+ fscache_invalidate(nfsi->fscache, &auxdata,
+ i_size_read(&nfsi->vfs_inode), flags);
+ }
}

/*
@@ -190,12 +143,6 @@ static inline const char *nfs_server_fscache_state(struct nfs_server *server)
}

#else /* CONFIG_NFS_FSCACHE */
-static inline int nfs_fscache_register(void) { return 0; }
-static inline void nfs_fscache_unregister(void) {}
-
-static inline void nfs_fscache_get_client_cookie(struct nfs_client *clp) {}
-static inline void nfs_fscache_release_client_cookie(struct nfs_client *clp) {}
-
static inline void nfs_fscache_release_super_cookie(struct super_block *sb) {}

static inline void nfs_fscache_init_inode(struct inode *inode) {}
@@ -207,11 +154,6 @@ static inline int nfs_fscache_release_page(struct page *page, gfp_t gfp)
{
return 1; /* True: may release page */
}
-static inline void nfs_fscache_invalidate_page(struct page *page,
- struct inode *inode) {}
-static inline void nfs_fscache_wait_on_page_write(struct nfs_inode *nfsi,
- struct page *page) {}
-
static inline int nfs_readpage_from_fscache(struct nfs_open_context *ctx,
struct inode *inode,
struct page *page)
@@ -230,8 +172,7 @@ static inline void nfs_readpage_to_fscache(struct inode *inode,
struct page *page, int sync) {}


-static inline void nfs_fscache_invalidate(struct inode *inode) {}
-static inline void nfs_fscache_wait_on_invalidate(struct inode *inode) {}
+static inline void nfs_fscache_invalidate(struct inode *inode, int flags) {}

static inline const char *nfs_server_fscache_state(struct nfs_server *server)
{
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index dd53704c3f40..ecf99ca48569 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -209,7 +209,7 @@ void nfs_set_cache_invalid(struct inode *inode, unsigned long flags)
if (!nfs_has_xattr_cache(nfsi))
flags &= ~NFS_INO_INVALID_XATTR;
if (flags & NFS_INO_INVALID_DATA)
- nfs_fscache_invalidate(inode);
+ nfs_fscache_invalidate(inode, 0);
flags &= ~(NFS_INO_REVAL_PAGECACHE | NFS_INO_REVAL_FORCED);

nfsi->cache_validity |= flags;
@@ -1288,6 +1288,7 @@ static int nfs_invalidate_mapping(struct inode *inode, struct address_space *map
{
int ret;

+ nfs_fscache_invalidate(inode, 0);
if (mapping->nrpages != 0) {
if (S_ISREG(inode->i_mode)) {
ret = nfs_sync_mapping(mapping);
@@ -1299,7 +1300,6 @@ static int nfs_invalidate_mapping(struct inode *inode, struct address_space *map
return ret;
}
nfs_inc_stats(inode, NFSIOS_DATAINVALIDATE);
- nfs_fscache_wait_on_invalidate(inode);

dfprintk(PAGECACHE, "NFS: (%s/%Lu) data cache invalidated\n",
inode->i_sb->s_id,
@@ -2373,10 +2373,6 @@ static int __init init_nfs_fs(void)
if (err < 0)
goto out9;

- err = nfs_fscache_register();
- if (err < 0)
- goto out8;
-
err = nfsiod_start();
if (err)
goto out7;
@@ -2428,8 +2424,6 @@ static int __init init_nfs_fs(void)
out6:
nfsiod_stop();
out7:
- nfs_fscache_unregister();
-out8:
unregister_pernet_subsys(&nfs_net_ops);
out9:
nfs_sysfs_exit();
@@ -2444,7 +2438,6 @@ static void __exit exit_nfs_fs(void)
nfs_destroy_readpagecache();
nfs_destroy_inodecache();
nfs_destroy_nfspagecache();
- nfs_fscache_unregister();
unregister_pernet_subsys(&nfs_net_ops);
rpc_proc_unregister(&init_net, "nfs");
unregister_nfs_fs();
diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index 3aced401735c..c96700f4b8a6 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -1211,7 +1211,6 @@ static void nfs_get_cache_cookie(struct super_block *sb,
char *uniq = NULL;
int ulen = 0;

- nfss->fscache_key = NULL;
nfss->fscache = NULL;

if (!ctx)
@@ -1221,9 +1220,9 @@ static void nfs_get_cache_cookie(struct super_block *sb,
struct nfs_server *mnt_s = NFS_SB(ctx->clone_data.sb);
if (!(mnt_s->options & NFS_OPTION_FSCACHE))
return;
- if (mnt_s->fscache_key) {
- uniq = mnt_s->fscache_key->key.uniquifier;
- ulen = mnt_s->fscache_key->key.uniq_len;
+ if (mnt_s->fscache_uniq) {
+ uniq = mnt_s->fscache_uniq;
+ ulen = strlen(uniq);
}
} else {
if (!(ctx->options & NFS_OPTION_FSCACHE))
diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 9b7619ce17a7..2b322170372a 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -294,6 +294,7 @@ static void nfs_grow_file(struct page *page, unsigned int offset, unsigned int c
nfs_inc_stats(inode, NFSIOS_EXTENDWRITE);
out:
spin_unlock(&inode->i_lock);
+ nfs_fscache_invalidate(inode, 0);
}

/* A writeback failed: mark the page as bad, and invalidate the page cache */
diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
index 2a9acbfe00f0..77b2dba27bbb 100644
--- a/include/linux/nfs_fs_sb.h
+++ b/include/linux/nfs_fs_sb.h
@@ -120,11 +120,6 @@ struct nfs_client {
* This is used to generate the mv0 callback address.
*/
char cl_ipaddr[48];
-
-#ifdef CONFIG_NFS_FSCACHE
- struct fscache_cookie *fscache; /* client index cache cookie */
-#endif
-
struct net *cl_net;
struct list_head pending_cb_stateids;
};
@@ -194,8 +189,8 @@ struct nfs_server {
struct nfs_auth_info auth_info; /* parsed auth flavors */

#ifdef CONFIG_NFS_FSCACHE
- struct nfs_fscache_key *fscache_key; /* unique key for superblock */
- struct fscache_cookie *fscache; /* superblock cookie */
+ struct fscache_volume *fscache; /* superblock cookie */
+ char *fscache_uniq; /* Uniquifier (or NULL) */
#endif

u32 pnfs_blksize; /* layout_blksize attr */