Commit 9b3f26c9 authored by David Howells's avatar David Howells

FS-Cache: Make kAFS use FS-Cache

The attached patch makes the kAFS filesystem in fs/afs/ use FS-Cache, and
through it any attached caches.  The kAFS filesystem will use caching
automatically if it's available.
Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
Acked-by: default avatarSteve Dickson <steved@redhat.com>
Acked-by: default avatarTrond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
Tested-by: default avatarDaire Byrne <Daire.Byrne@framestore.com>
parent 9ae326a6
......@@ -19,3 +19,11 @@ config AFS_DEBUG
See <file:Documentation/filesystems/afs.txt> for more information.
If unsure, say N.
config AFS_FSCACHE
bool "Provide AFS client caching support (EXPERIMENTAL)"
depends on EXPERIMENTAL
depends on AFS_FS=m && FSCACHE || AFS_FS=y && FSCACHE=y
help
Say Y here if you want AFS data to be cached locally on disk through
the generic filesystem cache manager
......@@ -2,7 +2,10 @@
# Makefile for Red Hat Linux AFS client.
#
afs-cache-$(CONFIG_AFS_FSCACHE) := cache.o
kafs-objs := \
$(afs-cache-y) \
callback.o \
cell.o \
cmservice.o \
......
This diff is collapsed.
/* AFS local cache management interface
*
* Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
* Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
......@@ -9,15 +9,4 @@
* 2 of the License, or (at your option) any later version.
*/
#ifndef AFS_CACHE_H
#define AFS_CACHE_H
#undef AFS_CACHING_SUPPORT
#include <linux/mm.h>
#ifdef AFS_CACHING_SUPPORT
#include <linux/cachefs.h>
#endif
#include "types.h"
#endif /* AFS_CACHE_H */
#include <linux/fscache.h>
......@@ -147,12 +147,11 @@ struct afs_cell *afs_cell_create(const char *name, char *vllist)
if (ret < 0)
goto error;
#ifdef AFS_CACHING_SUPPORT
/* put it up for caching */
cachefs_acquire_cookie(afs_cache_netfs.primary_index,
&afs_vlocation_cache_index_def,
cell,
&cell->cache);
#ifdef CONFIG_AFS_FSCACHE
/* put it up for caching (this never returns an error) */
cell->cache = fscache_acquire_cookie(afs_cache_netfs.primary_index,
&afs_cell_cache_index_def,
cell);
#endif
/* add to the cell lists */
......@@ -362,10 +361,9 @@ static void afs_cell_destroy(struct afs_cell *cell)
list_del_init(&cell->proc_link);
up_write(&afs_proc_cells_sem);
#ifdef AFS_CACHING_SUPPORT
cachefs_relinquish_cookie(cell->cache, 0);
#ifdef CONFIG_AFS_FSCACHE
fscache_relinquish_cookie(cell->cache, 0);
#endif
key_put(cell->anonymous_key);
kfree(cell);
......
......@@ -23,6 +23,9 @@ static void afs_invalidatepage(struct page *page, unsigned long offset);
static int afs_releasepage(struct page *page, gfp_t gfp_flags);
static int afs_launder_page(struct page *page);
static int afs_readpages(struct file *filp, struct address_space *mapping,
struct list_head *pages, unsigned nr_pages);
const struct file_operations afs_file_operations = {
.open = afs_open,
.release = afs_release,
......@@ -46,6 +49,7 @@ const struct inode_operations afs_file_inode_operations = {
const struct address_space_operations afs_fs_aops = {
.readpage = afs_readpage,
.readpages = afs_readpages,
.set_page_dirty = afs_set_page_dirty,
.launder_page = afs_launder_page,
.releasepage = afs_releasepage,
......@@ -101,37 +105,18 @@ int afs_release(struct inode *inode, struct file *file)
/*
* deal with notification that a page was read from the cache
*/
#ifdef AFS_CACHING_SUPPORT
static void afs_readpage_read_complete(void *cookie_data,
struct page *page,
void *data,
int error)
static void afs_file_readpage_read_complete(struct page *page,
void *data,
int error)
{
_enter("%p,%p,%p,%d", cookie_data, page, data, error);
_enter("%p,%p,%d", page, data, error);
if (error)
SetPageError(page);
else
/* if the read completes with an error, we just unlock the page and let
* the VM reissue the readpage */
if (!error)
SetPageUptodate(page);
unlock_page(page);
}
#endif
/*
* deal with notification that a page was written to the cache
*/
#ifdef AFS_CACHING_SUPPORT
static void afs_readpage_write_complete(void *cookie_data,
struct page *page,
void *data,
int error)
{
_enter("%p,%p,%p,%d", cookie_data, page, data, error);
unlock_page(page);
}
#endif
/*
* AFS read page from file, directory or symlink
......@@ -161,9 +146,9 @@ static int afs_readpage(struct file *file, struct page *page)
if (test_bit(AFS_VNODE_DELETED, &vnode->flags))
goto error;
#ifdef AFS_CACHING_SUPPORT
/* is it cached? */
ret = cachefs_read_or_alloc_page(vnode->cache,
#ifdef CONFIG_AFS_FSCACHE
ret = fscache_read_or_alloc_page(vnode->cache,
page,
afs_file_readpage_read_complete,
NULL,
......@@ -171,20 +156,21 @@ static int afs_readpage(struct file *file, struct page *page)
#else
ret = -ENOBUFS;
#endif
switch (ret) {
/* read BIO submitted and wb-journal entry found */
case 1:
BUG(); // TODO - handle wb-journal match
/* read BIO submitted (page in cache) */
case 0:
break;
/* no page available in cache */
case -ENOBUFS:
/* page not yet cached */
case -ENODATA:
_debug("cache said ENODATA");
goto go_on;
/* page will not be cached */
case -ENOBUFS:
_debug("cache said ENOBUFS");
default:
go_on:
offset = page->index << PAGE_CACHE_SHIFT;
len = min_t(size_t, i_size_read(inode) - offset, PAGE_SIZE);
......@@ -198,27 +184,25 @@ static int afs_readpage(struct file *file, struct page *page)
set_bit(AFS_VNODE_DELETED, &vnode->flags);
ret = -ESTALE;
}
#ifdef AFS_CACHING_SUPPORT
cachefs_uncache_page(vnode->cache, page);
#ifdef CONFIG_AFS_FSCACHE
fscache_uncache_page(vnode->cache, page);
#endif
BUG_ON(PageFsCache(page));
goto error;
}
SetPageUptodate(page);
#ifdef AFS_CACHING_SUPPORT
if (cachefs_write_page(vnode->cache,
page,
afs_file_readpage_write_complete,
NULL,
GFP_KERNEL) != 0
) {
cachefs_uncache_page(vnode->cache, page);
unlock_page(page);
/* send the page to the cache */
#ifdef CONFIG_AFS_FSCACHE
if (PageFsCache(page) &&
fscache_write_page(vnode->cache, page, GFP_KERNEL) != 0) {
fscache_uncache_page(vnode->cache, page);
BUG_ON(PageFsCache(page));
}
#else
unlock_page(page);
#endif
unlock_page(page);
}
_leave(" = 0");
......@@ -232,34 +216,59 @@ static int afs_readpage(struct file *file, struct page *page)
}
/*
* invalidate part or all of a page
* read a set of pages
*/
static void afs_invalidatepage(struct page *page, unsigned long offset)
static int afs_readpages(struct file *file, struct address_space *mapping,
struct list_head *pages, unsigned nr_pages)
{
int ret = 1;
struct afs_vnode *vnode;
int ret = 0;
_enter("{%lu},%lu", page->index, offset);
_enter(",{%lu},,%d", mapping->host->i_ino, nr_pages);
BUG_ON(!PageLocked(page));
vnode = AFS_FS_I(mapping->host);
if (vnode->flags & AFS_VNODE_DELETED) {
_leave(" = -ESTALE");
return -ESTALE;
}
if (PagePrivate(page)) {
/* We release buffers only if the entire page is being
* invalidated.
* The get_block cached value has been unconditionally
* invalidated, so real IO is not possible anymore.
*/
if (offset == 0) {
BUG_ON(!PageLocked(page));
ret = 0;
if (!PageWriteback(page))
ret = page->mapping->a_ops->releasepage(page,
0);
/* possibly should BUG_ON(!ret); - neilb */
}
/* attempt to read as many of the pages as possible */
#ifdef CONFIG_AFS_FSCACHE
ret = fscache_read_or_alloc_pages(vnode->cache,
mapping,
pages,
&nr_pages,
afs_file_readpage_read_complete,
NULL,
mapping_gfp_mask(mapping));
#else
ret = -ENOBUFS;
#endif
switch (ret) {
/* all pages are being read from the cache */
case 0:
BUG_ON(!list_empty(pages));
BUG_ON(nr_pages != 0);
_leave(" = 0 [reading all]");
return 0;
/* there were pages that couldn't be read from the cache */
case -ENODATA:
case -ENOBUFS:
break;
/* other error */
default:
_leave(" = %d", ret);
return ret;
}
_leave(" = %d", ret);
/* load the missing pages from the network */
ret = read_cache_pages(mapping, pages, (void *) afs_readpage, file);
_leave(" = %d [netting]", ret);
return ret;
}
/*
......@@ -273,25 +282,82 @@ static int afs_launder_page(struct page *page)
}
/*
* release a page and cleanup its private data
* invalidate part or all of a page
* - release a page and clean up its private data if offset is 0 (indicating
* the entire page)
*/
static void afs_invalidatepage(struct page *page, unsigned long offset)
{
struct afs_writeback *wb = (struct afs_writeback *) page_private(page);
_enter("{%lu},%lu", page->index, offset);
BUG_ON(!PageLocked(page));
/* we clean up only if the entire page is being invalidated */
if (offset == 0) {
#ifdef CONFIG_AFS_FSCACHE
if (PageFsCache(page)) {
struct afs_vnode *vnode = AFS_FS_I(page->mapping->host);
fscache_wait_on_page_write(vnode->cache, page);
fscache_uncache_page(vnode->cache, page);
ClearPageFsCache(page);
}
#endif
if (PagePrivate(page)) {
if (wb && !PageWriteback(page)) {
set_page_private(page, 0);
afs_put_writeback(wb);
}
if (!page_private(page))
ClearPagePrivate(page);
}
}
_leave("");
}
/*
* release a page and clean up its private state if it's not busy
* - return true if the page can now be released, false if not
*/
static int afs_releasepage(struct page *page, gfp_t gfp_flags)
{
struct afs_writeback *wb = (struct afs_writeback *) page_private(page);
struct afs_vnode *vnode = AFS_FS_I(page->mapping->host);
struct afs_writeback *wb;
_enter("{{%x:%u}[%lu],%lx},%x",
vnode->fid.vid, vnode->fid.vnode, page->index, page->flags,
gfp_flags);
/* deny if page is being written to the cache and the caller hasn't
* elected to wait */
#ifdef CONFIG_AFS_FSCACHE
if (PageFsCache(page)) {
if (fscache_check_page_write(vnode->cache, page)) {
if (!(gfp_flags & __GFP_WAIT)) {
_leave(" = F [cache busy]");
return 0;
}
fscache_wait_on_page_write(vnode->cache, page);
}
fscache_uncache_page(vnode->cache, page);
ClearPageFsCache(page);
}
#endif
if (PagePrivate(page)) {
wb = (struct afs_writeback *) page_private(page);
ASSERT(wb != NULL);
set_page_private(page, 0);
if (wb) {
set_page_private(page, 0);
afs_put_writeback(wb);
}
ClearPagePrivate(page);
afs_put_writeback(wb);
}
_leave(" = 0");
return 0;
/* indicate that the page can be released */
_leave(" = T");
return 1;
}
......@@ -61,6 +61,11 @@ static int afs_inode_map_status(struct afs_vnode *vnode, struct key *key)
return -EBADMSG;
}
#ifdef CONFIG_AFS_FSCACHE
if (vnode->status.size != inode->i_size)
fscache_attr_changed(vnode->cache);
#endif
inode->i_nlink = vnode->status.nlink;
inode->i_uid = vnode->status.owner;
inode->i_gid = 0;
......@@ -149,15 +154,6 @@ struct inode *afs_iget(struct super_block *sb, struct key *key,
return inode;
}
#ifdef AFS_CACHING_SUPPORT
/* set up caching before reading the status, as fetch-status reads the
* first page of symlinks to see if they're really mntpts */
cachefs_acquire_cookie(vnode->volume->cache,
NULL,
vnode,
&vnode->cache);
#endif
if (!status) {
/* it's a remotely extant inode */
set_bit(AFS_VNODE_CB_BROKEN, &vnode->flags);
......@@ -183,6 +179,15 @@ struct inode *afs_iget(struct super_block *sb, struct key *key,
}
}
/* set up caching before mapping the status, as map-status reads the
* first page of symlinks to see if they're really mountpoints */
inode->i_size = vnode->status.size;
#ifdef CONFIG_AFS_FSCACHE
vnode->cache = fscache_acquire_cookie(vnode->volume->cache,
&afs_vnode_cache_index_def,
vnode);
#endif
ret = afs_inode_map_status(vnode, key);
if (ret < 0)
goto bad_inode;
......@@ -196,6 +201,10 @@ struct inode *afs_iget(struct super_block *sb, struct key *key,
/* failure */
bad_inode:
#ifdef CONFIG_AFS_FSCACHE
fscache_relinquish_cookie(vnode->cache, 0);
vnode->cache = NULL;
#endif
iget_failed(inode);
_leave(" = %d [bad]", ret);
return ERR_PTR(ret);
......@@ -340,8 +349,8 @@ void afs_clear_inode(struct inode *inode)
ASSERT(list_empty(&vnode->writebacks));
ASSERT(!vnode->cb_promised);
#ifdef AFS_CACHING_SUPPORT
cachefs_relinquish_cookie(vnode->cache, 0);
#ifdef CONFIG_AFS_FSCACHE
fscache_relinquish_cookie(vnode->cache, 0);
vnode->cache = NULL;
#endif
......
......@@ -21,6 +21,7 @@
#include "afs.h"
#include "afs_vl.h"
#include "cache.h"
#define AFS_CELL_MAX_ADDRS 15
......@@ -193,8 +194,8 @@ struct afs_cell {
struct key *anonymous_key; /* anonymous user key for this cell */
struct list_head proc_link; /* /proc cell list link */
struct proc_dir_entry *proc_dir; /* /proc dir for this cell */
#ifdef AFS_CACHING_SUPPORT
struct cachefs_cookie *cache; /* caching cookie */
#ifdef CONFIG_AFS_FSCACHE
struct fscache_cookie *cache; /* caching cookie */
#endif
/* server record management */
......@@ -249,8 +250,8 @@ struct afs_vlocation {
struct list_head grave; /* link in master graveyard list */
struct list_head update; /* link in master update list */
struct afs_cell *cell; /* cell to which volume belongs */
#ifdef AFS_CACHING_SUPPORT
struct cachefs_cookie *cache; /* caching cookie */
#ifdef CONFIG_AFS_FSCACHE
struct fscache_cookie *cache; /* caching cookie */
#endif
struct afs_cache_vlocation vldb; /* volume information DB record */
struct afs_volume *vols[3]; /* volume access record pointer (index by type) */
......@@ -302,8 +303,8 @@ struct afs_volume {
atomic_t usage;
struct afs_cell *cell; /* cell to which belongs (unrefd ptr) */
struct afs_vlocation *vlocation; /* volume location */
#ifdef AFS_CACHING_SUPPORT
struct cachefs_cookie *cache; /* caching cookie */
#ifdef CONFIG_AFS_FSCACHE
struct fscache_cookie *cache; /* caching cookie */
#endif
afs_volid_t vid; /* volume ID */
afs_voltype_t type; /* type of volume */
......@@ -333,8 +334,8 @@ struct afs_vnode {
struct afs_server *server; /* server currently supplying this file */
struct afs_fid fid; /* the file identifier for this inode */
struct afs_file_status status; /* AFS status info for this file */
#ifdef AFS_CACHING_SUPPORT
struct cachefs_cookie *cache; /* caching cookie */
#ifdef CONFIG_AFS_FSCACHE
struct fscache_cookie *cache; /* caching cookie */
#endif
struct afs_permits *permits; /* cache of permits so far obtained */
struct mutex permits_lock; /* lock for altering permits list */
......@@ -427,6 +428,22 @@ struct afs_uuid {
};
/*****************************************************************************/
/*
* cache.c
*/
#ifdef CONFIG_AFS_FSCACHE
extern struct fscache_netfs afs_cache_netfs;
extern struct fscache_cookie_def afs_cell_cache_index_def;
extern struct fscache_cookie_def afs_vlocation_cache_index_def;
extern struct fscache_cookie_def afs_volume_cache_index_def;
extern struct fscache_cookie_def afs_vnode_cache_index_def;
#else
#define afs_cell_cache_index_def (*(struct fscache_cookie_def *) NULL)
#define afs_vlocation_cache_index_def (*(struct fscache_cookie_def *) NULL)
#define afs_volume_cache_index_def (*(struct fscache_cookie_def *) NULL)
#define afs_vnode_cache_index_def (*(struct fscache_cookie_def *) NULL)
#endif
/*
* callback.c
*/
......@@ -446,9 +463,6 @@ extern void afs_callback_update_kill(void);
*/
extern struct rw_semaphore afs_proc_cells_sem;
extern struct list_head afs_proc_cells;
#ifdef AFS_CACHING_SUPPORT
extern struct cachefs_index_def afs_cache_cell_index_def;
#endif
#define afs_get_cell(C) do { atomic_inc(&(C)->usage); } while(0)
extern int afs_cell_init(char *);
......@@ -554,9 +568,6 @@ extern void afs_clear_inode(struct inode *);
* main.c
*/
extern struct afs_uuid afs_uuid;
#ifdef AFS_CACHING_SUPPORT
extern struct cachefs_netfs afs_cache_netfs;
#endif
/*
* misc.c
......@@ -637,10 +648,6 @@ extern int afs_get_MAC_address(u8 *, size_t);
/*
* vlclient.c
*/
#ifdef AFS_CACHING_SUPPORT
extern struct cachefs_index_def afs_vlocation_cache_index_def;
#endif
extern int afs_vl_get_entry_by_name(struct in_addr *, struct key *,
const char *, struct afs_cache_vlocation *,
const struct afs_wait_mode *);
......@@ -664,12 +671,6 @@ extern void afs_vlocation_purge(void);
/*
* vnode.c
*/
#ifdef AFS_CACHING_SUPPORT
extern struct cachefs_index_def afs_vnode_cache_index_def;
#endif
extern struct afs_timer_ops afs_vnode_cb_timed_out_ops;
static inline struct afs_vnode *AFS_FS_I(struct inode *inode)
{
return container_of(inode, struct afs_vnode, vfs_inode);
......@@ -711,10 +712,6 @@ extern int afs_vnode_release_lock(struct afs_vnode *, struct key *);
/*
* volume.c
*/
#ifdef AFS_CACHING_SUPPORT
extern struct cachefs_index_def afs_volume_cache_index_def;
#endif
#define afs_get_volume(V) do { atomic_inc(&(V)->usage); } while(0)
extern void afs_put_volume(struct afs_volume *);
......
/* AFS client file system
*
* Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
* Copyright (C) 2002,5 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
......@@ -29,18 +29,6 @@ static char *rootcell;
module_param(rootcell, charp, 0);
MODULE_PARM_DESC(rootcell, "root AFS cell name and VL server IP addr list");
#ifdef AFS_CACHING_SUPPORT
static struct cachefs_netfs_operations afs_cache_ops = {
.get_page_cookie = afs_cache_get_page_cookie,
};
struct cachefs_netfs afs_cache_netfs = {
.name = "afs",
.version = 0,
.ops = &afs_cache_ops,
};
#endif
struct afs_uuid afs_uuid;
/*
......@@ -104,10 +92,9 @@ static int __init afs_init(void)
if (ret < 0)
return ret;
#ifdef AFS_CACHING_SUPPORT
#ifdef CONFIG_AFS_FSCACHE
/* we want to be able to cache */
ret = cachefs_register_netfs(&afs_cache_netfs,
&afs_cache_cell_index_def);
ret = fscache_register_netfs(&afs_cache_netfs);
if (ret < 0)
goto error_cache;
#endif
......@@ -142,8 +129,8 @@ static int __init afs_init(void)
error_open_socket:
error_vl_update_init:
error_cell_init:
#ifdef AFS_CACHING_SUPPORT
cachefs_unregister_netfs(&afs_cache_netfs);
#ifdef CONFIG_AFS_FSCACHE
fscache_unregister_netfs(&afs_cache_netfs);
error_cache:
#endif
afs_callback_update_kill();
......@@ -175,8 +162,8 @@ static void __exit afs_exit(void)
afs_vlocation_purge();
flush_scheduled_work();
afs_cell_purge();
#ifdef AFS_CACHING_SUPPORT
cachefs_unregister_netfs(&afs_cache_netfs);
#ifdef CONFIG_AFS_FSCACHE
fscache_unregister_netfs(&afs_cache_netfs);
#endif
afs_proc_cleanup();
rcu_barrier();
......
......@@ -173,9 +173,9 @@ static struct vfsmount *afs_mntpt_do_automount(struct dentry *mntpt)
if (PageError(page))
goto error;
buf = kmap(page);
buf = kmap_atomic(page, KM_USER0);
memcpy(devname, buf, size);
kunmap(page);
kunmap_atomic(buf, KM_USER0);
page_cache_release(page);
page = NULL;
......
......@@ -281,9 +281,8 @@ static void afs_vlocation_apply_update(struct afs_vlocation *vl,
vl->vldb = *vldb;
#ifdef AFS_CACHING_SUPPORT
/* update volume entry in local cache */
cachefs_update_cookie(vl->cache);
#ifdef CONFIG_AFS_FSCACHE
fscache_update_cookie(vl->cache);
#endif
}
......@@ -304,11 +303,9 @@ static int afs_vlocation_fill_in_record(struct afs_vlocation *vl,
memset(&vldb, 0, sizeof(vldb));
/* see if we have an in-cache copy (will set vl->valid if there is) */
#ifdef AFS_CACHING_SUPPORT
cachefs_acquire_cookie(cell->cache,
&afs_volume_cache_index_def,
vlocation,
&vl->cache);
#ifdef CONFIG_AFS_FSCACHE
vl->cache = fscache_acquire_cookie(vl->cell->cache,
&afs_vlocation_cache_index_def, vl);
#endif
if (vl->valid) {
......@@ -420,6 +417,11 @@ struct afs_vlocation *afs_vlocation_lookup(struct afs_cell *cell,
spin_unlock(&vl->lock);
wake_up(&vl->waitq);
/* update volume entry in local cache */
#ifdef CONFIG_AFS_FSCACHE
fscache_update_cookie(vl->cache);
#endif
/* schedule for regular updates */
afs_vlocation_queue_for_updates(vl);
goto success;
......@@ -465,7 +467,7 @@ struct afs_vlocation *afs_vlocation_lookup(struct afs_cell *cell,
spin_unlock(&vl->lock);
success:
_leave(" = %p",vl);
_leave(" = %p", vl);
return vl;
error_abandon:
......@@ -523,10 +525,9 @@ static void afs_vlocation_destroy(struct afs_vlocation *vl)
{
_enter("%p", vl);
#ifdef AFS_CACHING_SUPPORT
cachefs_relinquish_cookie(vl->cache, 0);
#ifdef CONFIG_AFS_FSCACHE
fscache_relinquish_cookie(vl->cache, 0);
#endif
afs_put_cell(vl->cell);
kfree(vl);
}
......
......@@ -124,13 +124,11 @@ struct afs_volume *afs_volume_lookup(struct afs_mount_params *params)
}
/* attach the cache and volume location */
#ifdef AFS_CACHING_SUPPORT
cachefs_acquire_cookie(vlocation->cache,
&afs_vnode_cache_index_def,
volume,
&volume->cache);
#ifdef CONFIG_AFS_FSCACHE
volume->cache = fscache_acquire_cookie(vlocation->cache,
&afs_volume_cache_index_def,
volume);
#endif
afs_get_vlocation(vlocation);
volume->vlocation = vlocation;
......@@ -194,8 +192,8 @@ void afs_put_volume(struct afs_volume *volume)
up_write(&vlocation->cell->vl_sem);
/* finish cleaning up the volume */
#ifdef AFS_CACHING_SUPPORT
cachefs_relinquish_cookie(volume->cache, 0);
#ifdef CONFIG_AFS_FSCACHE
fscache_relinquish_cookie(volume->cache, 0);
#endif
afs_put_vlocation(vlocation);
......
......@@ -780,3 +780,24 @@ int afs_fsync(struct file *file, struct dentry *dentry, int datasync)
_leave(" = %d", ret);
return ret;
}
/*
* notification that a previously read-only page is about to become writable
* - if it returns an error, the caller will deliver a bus error signal
*/
int afs_page_mkwrite(struct vm_area_struct *vma, struct page *page)
{
struct afs_vnode *vnode = AFS_FS_I(vma->vm_file->f_mapping->host);
_enter("{{%x:%u}},{%lx}",
vnode->fid.vid, vnode->fid.vnode, page->index);
/* wait for the page to be written to the cache before we allow it to
* be modified */